SherbyNet - /page/wikibook/entry.mu

Micron Document

<!DOCTYPE html>

<title>Chess clock</title>

</head>

<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Chess clock</span></span>

</h1>

</header>

/* start https://en.wikipedia.org/ */

.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}

/* end https://en.wikipedia.org/ */

</style><div role="note" class="hatnote navigation-not-searchable">This article is about the device with two adjacent clocks used in chess and other games. For a person who keeps track of the time during a sporting event, see <a href="Timekeeper" title="Timekeeper">Timekeeper</a>. For the instrument that determines time elapsed or time remaining in sporting events, see <a href="Game_clock_(sports)" class="mw-redirect" title="Game clock (sports)">Game clock (sports)</a>.</div>

<p>A <b>chess clock</b> is a device that comprises two adjacent <a href="Clock" title="Clock">clocks</a> with buttons to stop one clock while starting the other, so that the two clocks never run simultaneously. The clocks are used in <a href="Game" title="Game">games</a> where the time is allocated between two parties. The purpose is to keep track of the total time each party takes and prevent delays. Parties may take more or less time over any individual move.

</p><p>Chess clocks were first used extensively in tournament <a href="Chess" title="Chess">chess</a>, beginning with a competition at the <a href="London_1883_chess_tournament" title="London 1883 chess tournament">London 1883 tournament</a>. They are often called <b>game clocks</b>, as their use has since spread to tournament <a href="Scrabble" title="Scrabble">Scrabble</a>, <a href="Shogi" title="Shogi">shogi</a>, <a href="Go_(board_game)" class="mw-redirect" title="Go (board game)">Go</a>, and nearly every competitive two-player <a href="Board_game" title="Board game">board game</a>, as well as other types of games. Various designs exist for chess clocks and different methods of <a href="Time_control" title="Time control">time control</a> may be employed on the clocks, with "sudden death" being the simplest.

</p>

<div class="mw-heading mw-heading2"><h2 id="Description">Description</h2></div>

<p>A chess clock consists of two adjacent <a href="Clock" title="Clock">clocks</a> with buttons to stop one clock while starting the other, so that the two clocks never run simultaneously.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> The devices are used in <a href="Chess" title="Chess">chess</a> and other two-player <a href="Game" title="Game">games</a> where the players move in turn. The purpose is to keep track of the total time each player takes for their own moves, and ensure that neither player overly delays the game.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>

</p><p>Invented by Thomas Bright Wilson of Manchester Chess Club, the clocks were first used during competition at the <a href="London_1883_chess_tournament" title="London 1883 chess tournament">London 1883 tournament</a>.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> Chess clocks were first used extensively in tournament <a href="Chess" title="Chess">chess</a>, and are often called <i>game clocks</i>. Their use has since spread to tournament <a href="Scrabble" title="Scrabble">Scrabble</a>,<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> <a href="Shogi" title="Shogi">shogi</a>, <a href="Go_(board_game)" class="mw-redirect" title="Go (board game)">Go</a>, and nearly every competitive two-player <a href="Board_game" title="Board game">board game</a>, as well as other types of games. They have also been used in some legal settings where each side or party is allotted a specific amount of time for arguments.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="Designs">Designs</h2></div>

<div class="mw-heading mw-heading3"><h3 id="Analog_game_clocks">Analog game clocks</h3></div>

<p><a href="Analog_clock" class="mw-redirect" title="Analog clock">Analog clocks</a> are equipped with a "flag" that falls to indicate the exact moment the player's time has expired. Analog clocks use mechanical buttons. Pressing the button on one player's side physically stops the movement of that player's clock and releases the hold on the opponent's.

</p><p>The drawbacks of the mechanical clocks include accuracy and matching of the two clocks, and matching of the indicators (flags) of time expiration. Additional time cannot easily be added for more complex time controls, especially those that call for an increment or delay on every move, such as some forms of <a href="Byoyomi" class="mw-redirect" title="Byoyomi">byoyomi</a>.

</p>

<div class="mw-heading mw-heading3"><h3 id="Early_development_of_digital_game_clocks">Early development of digital game clocks</h3></div>

<p>In 1973, to address the issues with analog clocks, Bruce Cheney, a <a href="Cornell_University" title="Cornell University">Cornell University</a> electrical engineering (EE) student and chess player, created the first digital chess clock as a project for an undergraduate EE course.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Typical of most inventions, it was crude compared to the products on the market many years later and was limited by the technology that existed at the time. For example, the display was implemented via red LEDs, which required significant power and, as a result, the clock had to be plugged into a wall outlet. The high cost of LEDs at the time meant that only one set of digits could be displayed: that of the player whose turn it was to move. This meant that each player's time had to be multiplexed to the display when their time was running. In 1973, <a href="Large-Scale_Integration" class="mw-redirect" title="Large-Scale Integration">LSI</a> chips were not readily or cheaply available, so all the multiplexing and logic was enabled using chips consisting of four two-input <a href="Transistor%E2%80%93transistor_logic" title="Transistor–transistor logic">TTL NAND gates</a>, resulting in excessive power consumption. Being plugged into the wall is obviously a major drawback, but had one advantage: <a href="Utility_frequency#Stability" title="Utility frequency">the timebase for the clock was driven off a rectified version of the alternating current mains frequency</a>. Each player had a separate counter and, in a parallel to the original mechanical architecture, one player's counter was disabled while the other's was running. The clock only had one mode: time ran forward. It could be reset, but not set. It did not count the number of moves. But it successfully addressed the original goals of the project (accurate and matched timing).

</p><p>The first commercially available digital chess clock was patented in 1975 by Joseph Meshi and Jeffrey R. Ponsor. They named it the Micromate-80.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> There was only one made<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> and this was tested by chess players in multiple tournaments. Three years later a much-improved Micromate-180 was produced alongside Meshi's MBA <a href="Thesis" title="Thesis">thesis</a>, "Demand Analysis for a New Product (The Digital Chess Clock)", at <a href="San_Diego_State_University" title="San Diego State University">San Diego State University</a>, while Meshi and Ponsor continued to develop digital gaming.<sup id="cite_ref-:0_9-0" class="reference"><a href="#cite_note-:0-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading3"><h3 id="Fischer_clock_and_related_designs">Fischer clock and related designs </h3></div>

<p>Digital clocks and Internet gaming have spurred a wave of experimentation with more varied and complex time controls than the traditional standards. <a href="Time_control" title="Time control">Time control</a> is commonly used in modern chess in many different <a href="Time_control#Methodology" title="Time control">methodologies</a>. One particularly notable development, which has gained quite wide acceptance in chess, was proposed by former world champion <a href="Bobby_Fischer" title="Bobby Fischer">Bobby Fischer</a>, who in 1988 filed for US patent 4,884,255 (awarded in 1989) for a new type of digital chess clock. Fischer's digital clock gave each player a fixed period of time at the start of the game and then added a small amount after each move.<sup id="cite_ref-:1_10-0" class="reference"><a href="#cite_note-:1-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> Joseph Meshi called this "Accumulation" as it was a main feature of his patented Micromate-180 (US Patent 4,247,925 1978).<sup id="cite_ref-:0_9-1" class="reference"><a href="#cite_note-:0-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>

</p><p>The increment time control was first used in the privately organised <a href="Fischer%E2%80%93Spassky_(1992_match)" title="Fischer–Spassky (1992 match)">1992 Fischer–Spassky match</a>, and quickly became popular in the wider chess world, being subsequently used in the <a href="FIDE_World_Chess_Championship_1998" title="FIDE World Chess Championship 1998">FIDE World Chess Championship 1998</a>.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Nowadays most top level tournaments and tournaments outside the United States use Fischer's system. An increasing number of lower level tournaments in the US are also starting to use Fischer's system. Other aspects of Fischer's patent, such as a synthesized voice announcing how much time the players have, thus eliminating the need for them to keep looking at the clock, have not been adopted.<sup id="cite_ref-:1_10-1" class="reference"><a href="#cite_note-:1-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup>

</p><p>On March 10, 1994, a patent application was filed by inventors Frank A. Camaratta Jr. of Huntsville, Alabama, and William Goichberg of Salisbury Mills, New York, for a game timer especially suitable for playing the game of chess, which employed a (simple) "delay" feature. The game timer provides, among other features, a user-definable delay between the time the activation button is pressed and the time that the activated clock actually begins to count down. United States Patent 5,420,830 was issued on May 10, 1995, and subsequently assigned to the United States Chess Federation by the inventors. As with the Fischer clock, the benefit of the delay clock is to reduce the likelihood that a player with positional or material superiority will lose a match solely because of the expiration of time on that player's time clock.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> In the United States, delay is still widely used, but increment is becoming more popular.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="Timing_methods">Timing methods</h2></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="Time_control" title="Time control">Time control</a></div>

<p><b>Sudden death</b>: The simplest <a href="Time_control" title="Time control">time control</a> is "sudden death", in which players must make a predetermined number of moves in a certain amount of time or forfeit the game immediately. A particularly popular variant is <a href="Blitz_chess" class="mw-redirect" title="Blitz chess">blitz chess</a>, in which each player is given a short time, such as five minutes, on the clock in which to play the entire game.

</p><p><b>Increment</b> (also known as Bonus and Fischer since former World Chess Champion <a href="Bobby_Fischer" title="Bobby Fischer">Bobby Fischer</a> patented this timing method): a specified amount of time is added to the player's main time each move, unless the player's main time ran out before they completed their move. For example, if the time control is 90+30 (ninety minutes of main time per player with a thirty-second increment each move), each player gets an additional thirty seconds added to their main time for each move, unless the player's main time ran out first. Under <a href="FIDE" title="FIDE">FIDE</a> and US Chess rules, the increment is applied to the first move as well. For example, for 3+2 each player starts with three minutes and two seconds on the first move. Not all digital clocks automatically give the increment for move one and thus for those that don't, the increment time has to be added manually to the main time so each player gets the increment for move one. In <a href="Online_chess" title="Online chess">online chess</a>, players may make multiple <a href="Premove" title="Premove">premoves</a> (such as moving a knight back and forth) to give them additional time to think and/or avoid running out of time.

</p><p><b>Bronstein delay</b> (named after Grandmaster <a href="David_Bronstein" title="David Bronstein">David Bronstein</a> who invented this timing method): this timing method adds time but, unlike Increment, the maximum amount of time is not always added. If a player expends more than the specified delay then the entire delay is added to the player's clock, but if a player moves faster than the delay, only the exact amount of time expended by the player is added. For example, if the delay is ten seconds and a player uses ten or more seconds for a move, ten seconds is added after they complete their move. If the player uses five seconds for a move, five seconds is added after they complete their move. This ensures that the main time left on the clock can never increase even if a player makes fast moves. As with Increment, the delay time is applied to the first move under FIDE and US Chess rules.

</p><p><b>Simple delay</b> (also known as US delay): with this timing method, the clock waits for the delay period each move before the player's main time starts counting down. For example, if the delay is ten seconds, the clock waits for ten seconds each move before the main time starts counting down.

</p><p>Bronstein delay and Simple delay are very similar, but not equal. Mathematically, Bronstein delay and Simple delay are identical; the amount of time allotted to each player is equivalent at all stages of the game. For this reason, the two delays are interchangeable in the <a href="FIDE" title="FIDE">FIDE</a> laws of chess.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> In practice, however, Bronstein delay and Simple delay display time differently. In Bronstein delay, the amount of time is added <i>after</i> the move has been made; this distinction may be crucial when a player is running out of time.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup>

</p><p>The advantage of Bronstein delay is that a player can always quickly see exactly how much time they have for their next move without having to mentally add the main and delay time. The advantage of Simple delay is that a player can always tell whether the time that is counting down is the delay time or the main time. For example, in a game with a 5-second delay, when a player presses their clock with 1 second remaining, the clock will display with 1 second remaining, and the 5-second delay is counted separately on their next turn. In Bronstein, the 5 seconds are immediately added, and the clock will display 6 seconds. Simple delay is the form of delay most often used in the US, while Bronstein delay is the form of delay most often used in most other countries.

</p>

<div class="mw-heading mw-heading2"><h2 id="Strategy">Strategy</h2></div>

<p>The players may take more or less time over any individual move. The opening moves in chess are often played quickly due to their familiarity, which leaves the players more time to consider more complex and unfamiliar positions later. It is not unusual in slow chess games for a player to leave the table, but the clock of the absent player continues to run if it is their turn, or starts to run if their opponent makes a move.

</p>

/* start https://en.wikipedia.org/ */

.mw-parser-output .portalbox{padding:0;margin:0.5em 0;display:table;box-sizing:border-box;max-width:175px;list-style:none}.mw-parser-output .portalborder{border:1px solid var(--border-color-base,#a2a9b1);padding:0.1em;background:var(--background-color-neutral-subtle,#f8f9fa)}.mw-parser-output .portalbox-entry{display:table-row;font-size:85%;line-height:110%;height:1.9em;font-style:italic;font-weight:bold}.mw-parser-output .portalbox-image{display:table-cell;padding:0.2em;vertical-align:middle;text-align:center}.mw-parser-output .portalbox-link{display:table-cell;padding:0.2em 0.2em 0.2em 0.3em;vertical-align:middle}@media(min-width:720px){.mw-parser-output .portalleft{margin:0.5em 1em 0.5em 0}.mw-parser-output .portalright{clear:right;float:right;margin:0.5em 0 0.5em 1em}}

/* end https://en.wikipedia.org/ */

</style>

<ul><li><a href="Chess_equipment" title="Chess equipment">Chess equipment</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

/* start https://en.wikipedia.org/ */

.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}

/* end https://en.wikipedia.org/ */

</style><div class="reflist">

/* start https://en.wikipedia.org/ */

.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("./mw/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("./mw/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("./mw/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("./mw/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}

/* end https://en.wikipedia.org/ */

</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.chesscorner.com/tutorial/chess_clock/chess_clock.htm">"The Chess Clock"</a>. <i>www.chesscorner.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2020-01-06</span></span>.</cite></span>

</li>

<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.chesshouse.com/pages/how-to-operate-a-chess-clock">"How to Operate a Chess Clock - by Chess House"</a>. <i>Chess House</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-07-02</span></span>.</cite></span>

</li>

<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><cite id="CITEREFVidmar1960" class="citation book cs1"><a href="Milan_Vidmar" title="Milan Vidmar">Vidmar, Milan</a> (1960). <i>Goldene Schachzeiten: Erinnerungen</i>. W. de Gruyter. p. 10. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-3-11-002095-3</bdi>.</cite> <span class="cs1-hidden-error citation-comment"><code class="cs1-code">{{cite book}}</code>: </span><span class="cs1-hidden-error citation-comment">ISBN / Date incompatibility (help)</span></span>

</li>

<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><cite id="CITEREFFeinstein2022" class="citation web cs1">Feinstein, PJ (2022-12-01). <a rel="nofollow" class="external text" href="https://www.rd.com/list/obscure-scrabble-rules/">"13 Obscure Scrabble Rules Serious Players Need to Know"</a>. <i>Reader's Digest</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-05-19</span></span>.</cite></span>

</li>

<li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><cite id="CITEREFAbe2018" class="citation web cs1">Abe, Kirstin L. (December 2018). <a rel="nofollow" class="external text" href="https://www.iadclaw.org/assets/1/19/TrialTechniquesTactics_December_2018.pdf">"Up Against the Clock – Time Limits in Civil Trials"</a> <span class="cs1-format">(PDF)</span>. <i>International Association of Defense Counsel</i>. Page 2, note 1<span class="reference-accessdate">. Retrieved <span class="nowrap">2023-05-19</span></span>.</cite></span>

</li>

<li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text">"Early Bird", <i><a href="Chess_Life" title="Chess Life">Chess Life</a></i>, April 1992.</span>

</li>

/* start https://en.wikipedia.org/ */

.mw-parser-output .citation{word-wrap:break-word}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}

/* end https://en.wikipedia.org/ */

</style><span class="citation patent" id="CITEREFMeshi,_JosephPonsor,_Jeffrey_R.1977"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US4062180">US patent 4062180</a>, Meshi, Joseph & Ponsor, Jeffrey R., "Electronic chess clock", issued 1977-12-13</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=4062180&rft.cc=US&rft.title=Electronic+chess+clock&rft.inventor=Meshi%2C+Joseph&rft.date=1977-12-13&rft.appldate=1975-07-31"><span style="display: none;"> </span></span>; filed July 1975.</span>

</li>

<li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://gambiter.com/chess/chess_clock.html">"Chess clock - Rules and strategy of chess games"</a>. <i>gambiter.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2020-10-15</span></span>.</cite></span>

</li>

<li id="cite_note-:0-9"><span class="mw-cite-backlink">^ <a href="#cite_ref-:0_9-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:0_9-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><span class="citation patent" id="CITEREFMeshi,_JosephPonsor,_Jeffrey_R.1981"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US4247925">US patent 4247925</a>, Meshi, Joseph & Ponsor, Jeffrey R., "Game microcomputer", issued 1981-01-27</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=4247925&rft.cc=US&rft.title=Game+microcomputer&rft.inventor=Meshi%2C+Joseph&rft.date=1981-01-27&rft.appldate=1978-07-13"><span style="display: none;"> </span></span>; filed January 1978.</span>

</li>

<li id="cite_note-:1-10"><span class="mw-cite-backlink">^ <a href="#cite_ref-:1_10-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:1_10-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><span class="citation patent" id="CITEREFFisher,_Robert_J.1989"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US4884255">US patent 4884255</a>, Fisher, Robert J., "Digital chess clock", issued November 28, 1989</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=4884255&rft.cc=US&rft.title=Digital+chess+clock&rft.inventor=Fisher%2C+Robert+J.&rft.date=November 28, 1989&rft.appldate=August 5, 1988&rft.prioritydate=August 5, 1988"><span style="display: none;"> </span></span>, filed August 5, 1988.</span>

</li>

<li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://theweekinchess.com/html/twic161.html">The Week in Chess 161</a>, <a href="The_Week_in_Chess" title="The Week in Chess">The Week in Chess</a>, 8-Dec-1997</span>

</li>

<li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><span class="citation patent" id="CITEREFJrGoichberg1995"><a rel="nofollow" class="external text" href="https://patents.google.com/patent/US5420830/en">US5420830A</a>, Jr, Frank A. Camaratta & Goichberg, William, "Chess clock", issued 1995-05-30</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=US5420830A&rft.cc=&rft.title=Chess+clock&rft.inventor=Jr&rft.date=1995-05-30"><span style="display: none;"> </span></span></span>

</li>

<li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://new.uschess.org/rule-book-updates-and-changes">"Rule Book Updates and Changes"</a>. <i>US Chess.org</i>. 2021-09-28<span class="reference-accessdate">. Retrieved <span class="nowrap">2023-07-15</span></span>.</cite></span>

</li>

<li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://handbook.fide.com/chapter/E012023">"E. Miscellaneous / 01. Laws of Chess / FIDE Laws of Chess taking effect from 1 January 2023 / FIDE Handbook"</a>. <i>International Chess Federation (FIDE)</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2025-02-02</span></span>.</cite></span>

</li>

<li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.chicagopoint.com/clock2013.html">"Simple Delay Setting Replaces Bronstein in US Clock Rules"</a>. <i>www.chicagopoint.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2024-01-01</span></span>. <q>For the most part, both methods are substantially the same in terms of the amount of time players get and consume. At the end of the move, after the clock is hit, the remaining reserve time will be identical with Bronstein and Simple Delay. The difference is in the time available to complete the current move and becomes apparent when the reserve time runs down close to zero. Because Bronstein does not award the per-move allotment until after the move has been completed, you can run out of time and lose the match before getting the per-move allotment for the current move.</q></cite></span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2></div>

<ul><li><cite id="CITEREFKeith_Ammann2012" class="citation journal cs1">Keith Ammann (April 2012). "Winding Down: This year's rule changes may begin the last chapter in the history of the analog clock". <i><a href="Chess_Life" title="Chess Life">Chess Life</a></i>.</cite></li></ul>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

/* start https://en.wikipedia.org/ */

.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .infobox .side-box{font-size:100%}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}

/* end https://en.wikipedia.org/ */

</style><style data-mw-deduplicate="TemplateStyles:r1237033735">

/* start https://en.wikipedia.org/ */

@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}

/* end https://en.wikipedia.org/ */

</style><div class="side-box side-box-right sistersitebox"><style data-mw-deduplicate="TemplateStyles:r1126788409">

/* start https://en.wikipedia.org/ */

.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}

/* end https://en.wikipedia.org/ */

</style>

<div class="side-box-text plainlist">Wikimedia Commons has media related to <span style="font-weight: bold; font-style: italic;"><a href="https://commons.wikimedia.org/wiki/Category:Chess_clocks" class="extiw external" title="commons:Category:Chess clocks">Chess clocks</a></span>.</div></div>

</div>

<div class="side-box-text plainlist">Look up <i><b><a href="https://en.wiktionary.org/wiki/Special:Search/chess_clock" class="extiw external" title="wiktionary:Special:Search/chess clock">chess clock</a></b></i> in Wiktionary, the free dictionary.</div></div>

</div>

<ul><li><span><a rel="nofollow" class="external text" href="https://patents.google.com/patent/US4884255">U.S. patent 4,884,255</a></span> for Fischer's clock</li>

<li><a rel="nofollow" class="external text" href="http://ChessBullet.com/">Online Chess Clock / Chess Timer Example, used for Fast Chess</a></li>

<li><a rel="nofollow" class="external text" href="http://chessclock.org/">Online chess clock that implements Fischer and Bronstein timing methods</a></li></ul>

/* start https://en.wikipedia.org/ */

.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}

/* end https://en.wikipedia.org/ */

</style><style data-mw-deduplicate="TemplateStyles:r1236075235">

/* start https://en.wikipedia.org/ */

.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}

/* end https://en.wikipedia.org/ */

</style></div><div role="navigation" class="navbox" aria-labelledby="Chess445" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><style data-mw-deduplicate="TemplateStyles:r1239400231">

/* start https://en.wikipedia.org/ */

.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}

/* end https://en.wikipedia.org/ */

</style><div id="Chess445" style="font-size:114%;margin:0 4em"><a href="Chess" title="Chess">Chess</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Outline_of_chess" title="Outline of chess">Outline</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Chess_theory" title="Chess theory">Chess theory</a></li>

<li><a href="Chess_title" title="Chess title">Chess titles</a>

<ul><li><a href="Grandmaster_(chess)" title="Grandmaster (chess)">Grandmaster</a></li></ul></li>

<li><a href="Computer_chess" title="Computer chess">Computer chess</a>

<ul><li><a href="Glossary_of_computer_chess_terms" title="Glossary of computer chess terms">glossary</a></li>

<li><a href="Human%E2%80%93computer_chess_matches" title="Human–computer chess matches">matches</a></li>

<li><a href="Chess_engine" title="Chess engine">engines</a></li>

<li><a href="List_of_chess_software" title="List of chess software">software</a></li></ul></li>

<li><a href="Correspondence_chess" title="Correspondence chess">Correspondence chess</a></li>

<li><a href="Glossary_of_chess" title="Glossary of chess">Glossary</a></li>

<li><a href="Online_chess" title="Online chess">Online chess</a>

<ul><li><a href="Premove" title="Premove">Premove</a></li>

<li><a href="Internet_chess_server" class="mw-redirect" title="Internet chess server">Internet chess server</a>

<li><a href="Chess_rating_system" title="Chess rating system">Rating system</a>

<ul><li><a href="FIDE_world_rankings" class="mw-redirect" title="FIDE world rankings">world rankings</a></li>

<li><a href="Norm_(chess)" title="Norm (chess)">norms</a></li></ul></li>

<li><a href="Chess_variant" title="Chess variant">Variants</a>

<li><a href="List_of_world_records_in_chess" title="List of world records in chess">World records</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Chess_equipment" title="Chess equipment">Equipment</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Chess_set" title="Chess set">Chess set</a>

<ul><li><a href="Chessboard" title="Chessboard">chessboard</a></li>

<li><a href="Dubrovnik_chess_set" title="Dubrovnik chess set">Dubrovnik chess set</a></li>

<li><a href="Staunton_chess_set" title="Staunton chess set">Staunton chess set</a></li></ul></li>

<li><a href="Chess_piece" title="Chess piece">Chess pieces</a>

<li><a href="Queen_(chess)" title="Queen (chess)">Queen</a></li>

<li><a href="Bishop_(chess)" title="Bishop (chess)">Bishop</a></li>

<li><a href="Knight_(chess)" title="Knight (chess)">Knight</a></li>

<li><a href="Fairy_chess_piece" title="Fairy chess piece">Fairy</a></li></ul></li>

<li><a href="Chess_table" title="Chess table">Chess table</a></li>

<li><dfn><a href="Glossary_of_chess#score_sheets" title="Glossary of chess"><span title="See entry at: Glossary of chess § Score sheets" style="color:inherit;" class="glossary-link">Score sheets</span></a></dfn></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="History_of_chess" title="History of chess">History</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Timeline_of_chess" title="Timeline of chess">Timeline</a>

<ul><li><i><a href="Versus_de_scachis" title="Versus de scachis">Versus de scachis</a></i></li>

<li><i><a href="G%C3%B6ttingen_manuscript" title="Göttingen manuscript">Göttingen manuscript</a></i></li>

<li><a href="Charlemagne_chessmen" title="Charlemagne chessmen">Charlemagne chessmen</a></li>

<li><a href="Lewis_chessmen" title="Lewis chessmen">Lewis chessmen</a></li>

<li><a href="Romantic_chess" title="Romantic chess">Romantic chess</a></li>

<li><a href="Hypermodernism_(chess)" title="Hypermodernism (chess)">Hypermodernism</a></li>

<li><a href="Soviet_chess_school" title="Soviet chess school">Soviet chess school</a></li>

<li><a href="Comparison_of_top_chess_players_throughout_history" title="Comparison of top chess players throughout history">Top player comparison</a></li></ul></li>

<li><a href="Geography_of_chess" title="Geography of chess">Geography of chess</a>

<ul><li><a href="Chess_in_Africa" title="Chess in Africa">Africa</a>

<ul><li><a href="Chess_in_South_Africa" title="Chess in South Africa">South Africa</a></li></ul></li>

<li><a href="Chess_in_China" title="Chess in China">China</a></li>

<li><a href="Chess_in_Europe" title="Chess in Europe">Europe</a>

<ul><li><a href="Chess_in_Armenia" title="Chess in Armenia">Armenia</a></li>

<li><a href="Chess_in_Spain" title="Chess in Spain">Spain</a></li></ul></li>

<li><a href="Chess_in_India" title="Chess in India">India</a></li></ul></li>

<li><a href="List_of_chess_games" title="List of chess games">Notable games</a></li>

<li><a href="List_of_chess_players" title="List of chess players">List of chess players</a>

<ul><li><a href="List_of_amateur_chess_players" title="List of amateur chess players">amateurs</a></li>

<li><a href="List_of_female_chess_players" title="List of female chess players">female</a></li>

<li><a href="List_of_chess_grandmasters" title="List of chess grandmasters">grandmasters</a></li></ul></li>

<li><a href="Women_in_chess" title="Women in chess">Women in chess</a></li>

<li><a href="Transgender_people_in_chess" title="Transgender people in chess">Transgender people in chess</a></li>

<li>Chess museums

<ul><li><a href="Bobby_Fischer_Center" title="Bobby Fischer Center">Bobby Fischer Center</a></li>

<li><a href="G%C3%B6kyay_Association_Chess_Museum" title="Gökyay Association Chess Museum">Gökyay Association Chess Museum</a></li>

<li><a href="World_Chess_Hall_of_Fame" title="World Chess Hall of Fame">World Chess Hall of Fame</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Rules_of_chess" title="Rules of chess">Rules</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Castling" title="Castling">Castling</a></li>

<li><a href="Cheating_in_chess" title="Cheating in chess">Cheating in chess</a></li>

<li><a href="Check_(chess)" title="Check (chess)">Check</a></li>

<li><a href="Checkmate" title="Checkmate">Checkmate</a></li>

<ul><li><a href="Draw_by_agreement" title="Draw by agreement">by agreement</a></li>

<li><a href="Fifty-move_rule" title="Fifty-move rule">Fifty-move rule</a></li>

<li><a href="Perpetual_check" title="Perpetual check">Perpetual check</a></li>

<li><a href="Stalemate" title="Stalemate">Stalemate</a></li>

<li><a href="Threefold_repetition" title="Threefold repetition">Threefold repetition</a></li></ul></li>

<li><i><a href="En_passant" title="En passant">En passant</a></i></li>

<li><a href="Promotion_(chess)" title="Promotion (chess)">Pawn promotion</a></li>

<li><a href="Time_control" title="Time control">Time control</a>

<ul><li><a href="Fast_chess" title="Fast chess">Fast chess</a></li></ul></li>

<li><a href="Touch-move_rule" title="Touch-move rule">Touch-move rule</a></li>

<li><a href="White_and_Black_in_chess" title="White and Black in chess">White and Black</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Glossary_of_chess" title="Glossary of chess">Terms</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Blunder_(chess)" title="Blunder (chess)">Blunder</a></li>

<li><a href="Chess_notation" title="Chess notation">Chess notation</a>

<ul><li><a href="Algebraic_notation_(chess)" title="Algebraic notation (chess)">algebraic</a></li>

<li><a href="Descriptive_notation" title="Descriptive notation">descriptive</a></li>

<li><a href="Chess_annotation_symbols" title="Chess annotation symbols">annotation symbols</a></li>

<li><a href="Chess_symbols_in_Unicode" title="Chess symbols in Unicode">symbols in Unicode</a></li></ul></li>

<li><a href="Fianchetto" title="Fianchetto">Fianchetto</a></li>

<li><a href="Gambit" title="Gambit">Gambit</a></li>

<li><a href="Key_square" title="Key square">Key square</a></li>

<li><a href="Outpost_(chess)" title="Outpost (chess)">Outpost</a></li>

<li><a href="Pawn_(chess)" title="Pawn (chess)">Pawns</a>

<ul><li><a href="Backward_pawn" title="Backward pawn">backward</a></li>

<li><a href="Connected_pawns" title="Connected pawns">connected</a></li>

<li><a href="Doubled_pawns" title="Doubled pawns">doubled</a></li>

<li><a href="Isolated_pawn" title="Isolated pawn">isolated</a></li>

<li><a href="Passed_pawn" title="Passed pawn">passed</a></li></ul></li>

<li><a href="Swindle_(chess)" title="Swindle (chess)">Swindle</a></li>

<li><a href="Tempo_(chess)" title="Tempo (chess)">Tempo</a></li>

<li><a href="Transposition_(chess)" title="Transposition (chess)">Transposition</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Chess_tactic" title="Chess tactic">Tactics</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Castling#Artificial_castling" title="Castling">Artificial castling</a></li>

<li><a href="Battery_(chess)" title="Battery (chess)">Battery</a>

<ul><li><a href="Alekhine's_gun" title="Alekhine's gun">Alekhine's gun</a></li></ul></li>

<li><a href="Block_(chess)" title="Block (chess)">Block</a></li>

<li><a href="Checkmate_pattern" title="Checkmate pattern">Checkmate patterns</a></li>

<li><a href="Combination_(chess)" title="Combination (chess)">Combination</a></li>

<li><a href="Decoy_(chess)" title="Decoy (chess)">Decoy</a></li>

<li><a href="Deflection_(chess)" title="Deflection (chess)">Deflection</a></li>

<li><a href="Desperado_(chess)" title="Desperado (chess)">Desperado</a></li>

<li><a href="Discovered_attack" title="Discovered attack">Discovered attack</a></li>

<li><a href="Double_check" title="Double check">Double check</a></li>

<li><a href="Interference_(chess)" title="Interference (chess)">Interference</a></li>

<li><a href="Overloading_(chess)" title="Overloading (chess)">Overloading</a></li>

<li><a href="Pawn_storm" title="Pawn storm">Pawn storm</a></li>

<li><a href="Sacrifice_(chess)" title="Sacrifice (chess)">Sacrifice</a>

<ul><li><a href="Queen_sacrifice" title="Queen sacrifice">Queen sacrifice</a></li></ul></li>

<li><a href="Skewer_(chess)" title="Skewer (chess)">Skewer</a></li>

<li><a href="Undermining_(chess)" title="Undermining (chess)">Undermining</a></li>

<li><a href="Windmill_(chess)" title="Windmill (chess)">Windmill</a></li>

<li><a href="Zwischenzug" title="Zwischenzug">Zwischenzug</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Chess_strategy" title="Chess strategy">Strategy</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Compensation_(chess)" title="Compensation (chess)">Compensation</a></li>

<li><a href="Exchange_(chess)" title="Exchange (chess)">Exchange</a>

<ul><li><a href="The_exchange_(chess)" title="The exchange (chess)">the exchange</a></li></ul></li>

<li><a href="Initiative_(chess)" title="Initiative (chess)">Initiative</a>

<ul><li><a href="First-move_advantage_in_chess" title="First-move advantage in chess">first-move advantage</a></li></ul></li>

<li><a href="Chess_middlegame" title="Chess middlegame">Middlegame</a></li>

<li><a href="Pawn_structure" title="Pawn structure">Pawn structure</a>

<ul><li><a href="Hedgehog_(chess)" title="Hedgehog (chess)">Hedgehog</a></li>

<li><a href="Isolated_pawn" title="Isolated pawn">Isolated Queen's Pawn</a></li>

<li><a href="Mar%C3%B3czy_Bind" title="Maróczy Bind">Maróczy Bind</a></li>

<li><a href="Minority_attack" title="Minority attack">Minority attack</a></li></ul></li>

<li><a href="Chess_piece_relative_value" title="Chess piece relative value">Piece values</a></li>

<li><a href="Prophylaxis_(chess)" title="Prophylaxis (chess)">Prophylaxis</a></li>

<li><a href="School_of_chess" title="School of chess">School of chess</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Chess_opening" title="Chess opening">Openings</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Flank_opening" title="Flank opening">Flank opening</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="King's_Fianchetto_Opening" title="King's Fianchetto Opening">Benko Opening</a></li>

<li><a href="Bird's_Opening" title="Bird's Opening">Bird's Opening</a></li>

<li><a href="Dunst_Opening" title="Dunst Opening">Dunst Opening</a></li>

<li><a href="English_Opening" title="English Opening">English Opening</a></li>

<li><a href="Grob's_Attack" title="Grob's Attack">Grob's Attack</a></li>

<li><a href="Larsen's_Opening" class="mw-redirect" title="Larsen's Opening">Larsen's Opening</a></li>

<li><a href="Zukertort_Opening" title="Zukertort Opening">Zukertort Opening</a>

<ul><li><a href="King's_Indian_Attack" title="King's Indian Attack">King's Indian Attack</a></li>

<li><a href="R%C3%A9ti_Opening" title="Réti Opening">Réti Opening</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="King's_Pawn_Game" title="King's Pawn Game">King's Pawn Game</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Alekhine's_Defence" title="Alekhine's Defence">Alekhine's Defence</a></li>

<li><a href="Caro%E2%80%93Kann_Defence" title="Caro–Kann Defence">Caro–Kann Defence</a></li>

<li><a href="French_Defence" title="French Defence">French Defence</a></li>

<li><a href="Modern_Defense" title="Modern Defense">Modern Defence</a></li>

<li><a href="Nimzowitsch_Defence" title="Nimzowitsch Defence">Nimzowitsch Defence</a></li>

<ul><li><a href="Four_Knights_Game" title="Four Knights Game">Four Knights Game</a></li>

<li><a href="Giuoco_Piano" title="Giuoco Piano">Giuoco Piano</a></li>

<li><a href="Italian_Game" title="Italian Game">Italian Game</a></li>

<li><a href="King's_Gambit" title="King's Gambit">King's Gambit</a></li>

<li><a href="Petrov's_Defence" title="Petrov's Defence">Petrov's Defence</a></li>

<li><a href="Philidor_Defence" title="Philidor Defence">Philidor Defence</a></li>

<li><a href="Ponziani_Opening" title="Ponziani Opening">Ponziani Opening</a></li>

<li><a href="Ruy_Lopez" title="Ruy Lopez">Ruy Lopez</a></li>

<li><a href="Semi-Italian_Opening" title="Semi-Italian Opening">Semi-Italian Opening</a></li>

<li><a href="Scotch_Game" title="Scotch Game">Scotch Game</a></li>

<li><a href="Two_Knights_Defense" title="Two Knights Defense">Two Knights Defense</a></li>

<li><a href="Vienna_Game" title="Vienna Game">Vienna Game</a></li></ul></li>

<li><a href="Owen's_Defence" title="Owen's Defence">Owen's Defence</a></li>

<li><a href="Pirc_Defence" title="Pirc Defence">Pirc Defence</a>

<ul><li><a href="Pirc_Defence%2C_Austrian_Attack" title="Pirc Defence, Austrian Attack">Austrian Attack</a></li></ul></li>

<li><a href="Scandinavian_Defense" title="Scandinavian Defense">Scandinavian Defense</a></li>

<li><a href="Sicilian_Defence" title="Sicilian Defence">Sicilian Defence</a>

<ul><li><a href="Sicilian_Defence%2C_Alapin_Variation" title="Sicilian Defence, Alapin Variation">Alapin</a></li>

<li><a href="Sicilian_Defence%2C_Dragon_Variation" title="Sicilian Defence, Dragon Variation">Dragon</a>/<a href="Sicilian_Defence%2C_Accelerated_Dragon" title="Sicilian Defence, Accelerated Dragon">Accelerated Dragon</a></li>

<li><a href="Sicilian_Defence%2C_Najdorf_Variation" title="Sicilian Defence, Najdorf Variation">Najdorf</a></li>

<li><a href="Sicilian_Defence%2C_Scheveningen_Variation" title="Sicilian Defence, Scheveningen Variation">Scheveningen</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Queen's_Pawn_Game" title="Queen's Pawn Game">Queen's Pawn Game</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Budapest_Gambit" title="Budapest Gambit">Budapest Gambit</a></li>

<li><a href="Colle_System" title="Colle System">Colle System</a></li>

<li><a href="Dutch_Defence" title="Dutch Defence">Dutch Defence</a></li>

<li><a href="English_Defence" title="English Defence">English Defence</a></li>

<li><a href="Indian_Defence" title="Indian Defence">Indian Defence</a>

<ul><li><a href="Benoni_Defense" title="Benoni Defense">Benoni Defence</a></li>

<li><a href="Modern_Benoni" title="Modern Benoni">Modern Benoni</a></li>

<li><a href="Bogo-Indian_Defence" title="Bogo-Indian Defence">Bogo-Indian Defence</a></li>

<li><a href="Catalan_Opening" title="Catalan Opening">Catalan Opening</a></li>

<li><a href="Gr%C3%BCnfeld_Defence" title="Grünfeld Defence">Grünfeld Defence</a></li>

<li><a href="King's_Indian_Defence" title="King's Indian Defence">King's Indian Defence</a></li>

<li><a href="Nimzo-Indian_Defence" title="Nimzo-Indian Defence">Nimzo-Indian Defence</a></li>

<li><a href="Old_Indian_Defense" title="Old Indian Defense">Old Indian Defense</a></li>

<li><a href="Queen's_Indian_Defense" title="Queen's Indian Defense">Queen's Indian Defence</a></li></ul></li>

<li><a href="London_System" title="London System">London System</a></li>

<li><a href="Richter%E2%80%93Veresov_Attack" title="Richter–Veresov Attack">Richter–Veresov Attack</a></li>

<li><a href="Queen's_Gambit" title="Queen's Gambit">Queen's Gambit</a>

<ul><li><a href="Queen's_Gambit_Accepted" title="Queen's Gambit Accepted">Accepted</a></li>

<li><a href="Queen's_Gambit_Declined" title="Queen's Gambit Declined">Declined</a></li>

<li><a href="Slav_Defense" title="Slav Defense">Slav Defence</a></li>

<li><a href="Semi-Slav_Defense" title="Semi-Slav Defense">Semi-Slav Defence</a></li>

<li><a href="Chigorin_Defense" title="Chigorin Defense">Chigorin Defense</a></li></ul></li>

<li><a href="Torre_Attack" title="Torre Attack">Torre Attack</a></li>

<li><a href="Trompowsky_Attack" title="Trompowsky Attack">Trompowsky Attack</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="List_of_chess_openings" title="List of chess openings">List of openings</a>

<ul><li><a href="Chess_opening_theory_table" title="Chess opening theory table">theory table</a></li></ul></li>

<li><a href="List_of_chess_gambits" title="List of chess gambits">List of chess gambits</a></li>

<li><a href="Irregular_chess_opening" title="Irregular chess opening">Irregular</a>

<ul><li><a href="Bongcloud_Attack" title="Bongcloud Attack">Bongcloud Attack</a></li>

<li><a href="Scholar's_mate" title="Scholar's mate">Scholar's mate</a></li></ul></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Chess_endgame" title="Chess endgame">Endgames</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Bishop_and_knight_checkmate" title="Bishop and knight checkmate">Bishop and knight checkmate</a></li>

<li><a href="Opposite-colored_bishops_endgame" title="Opposite-colored bishops endgame">Opposite-coloured bishops</a></li>

<li><a href="Pawnless_chess_endgame" title="Pawnless chess endgame">Pawnless endgame</a></li>

<li><a href="Queen_and_pawn_versus_queen_endgame" title="Queen and pawn versus queen endgame">Queen and pawn vs. queen</a></li>

<li><a href="Queen_versus_pawn_endgame" title="Queen versus pawn endgame">Queen vs. pawn</a></li>

<li><a href="Queen_versus_rook_endgame" title="Queen versus rook endgame">Queen vs. rook</a></li>

<li><a href="Rook_and_bishop_versus_rook_endgame" title="Rook and bishop versus rook endgame">Rook and bishop vs. rook</a></li>

<ul><li><a href="Lucena_position" title="Lucena position">Lucena position</a></li>

<li><a href="Philidor_position" title="Philidor position">Philidor position</a></li></ul></li>

<li>Strategy

<ul><li><a href="Fortress_(chess)" title="Fortress (chess)">fortress</a></li>

<li><a href="Opposition_(chess)" title="Opposition (chess)">opposition</a></li>

<li><a href="Tarrasch_rule" title="Tarrasch rule">Tarrasch rule</a></li>

<li><a href="Triangulation_(chess)" title="Triangulation (chess)">triangulation</a></li>

<li><a href="Zugzwang" title="Zugzwang">Zugzwang</a></li></ul></li>

<li><a href="Endgame_study" title="Endgame study">Study</a></li>

<li><a href="Endgame_tablebase" title="Endgame tablebase">Tablebase</a></li>

<li><a href="Two_knights_endgame" title="Two knights endgame">Two knights endgame</a></li>

<li><a href="Wrong_bishop" title="Wrong bishop">Wrong bishop</a></li>

<li><a href="Wrong_rook_pawn" title="Wrong rook pawn">Wrong rook pawn</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Chess_tournament" title="Chess tournament">Tournaments</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="List_of_strong_chess_tournaments" title="List of strong chess tournaments">List of strong chess tournaments</a></li>

<li><a href="Chess_Olympiad" title="Chess Olympiad">Chess Olympiad</a>

<ul><li><a href="Women's_Chess_Olympiad" title="Women's Chess Olympiad">Women</a></li></ul></li>

<li><a href="World_Chess_Championship" title="World Chess Championship">World Chess Championship</a>

<li><a href="Candidates_Tournament" title="Candidates Tournament">Candidates Tournament</a></li>

<li><a href="Chess_World_Cup" title="Chess World Cup">Chess World Cup</a></li>

<li><a href="FIDE_Grand_Prix" title="FIDE Grand Prix">FIDE Grand Prix</a></li></ul></li>

<li>Other world championships

<ul><li><a href="Women's_World_Chess_Championship" title="Women's World Chess Championship">Women</a></li>

<li><a href="World_Rapid_Chess_Championship" title="World Rapid Chess Championship">Rapid</a></li>

<li><a href="World_Blitz_Chess_Championship" title="World Blitz Chess Championship">Blitz</a></li>

<li><a href="World_Junior_Chess_Championship" title="World Junior Chess Championship">Junior</a></li>

<li><a href="World_Youth_Chess_Championship" title="World Youth Chess Championship">Youth</a></li>

<li><a href="World_Senior_Chess_Championship" title="World Senior Chess Championship">Senior</a></li>

<li><a href="World_Amateur_Chess_Championship" title="World Amateur Chess Championship">Amateur</a></li>

<li><a href="World_Championship_of_Chess_Composition" title="World Championship of Chess Composition">Chess composition</a></li>

<li><a href="World_Chess_Solving_Championship" title="World Chess Solving Championship">Solving</a></li></ul></li>

<li>Computer chess championships

<li><a href="North_American_Computer_Chess_Championship" title="North American Computer Chess Championship">North American</a></li>

<li><a href="World_Computer_Speed_Chess_Championship" title="World Computer Speed Chess Championship">WCSCC</a></li></ul></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Art and media</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Ca%C3%AFssa" title="Caïssa">Caïssa</a></li>

<li><a href="Chess_aesthetics" title="Chess aesthetics">Chess aesthetics</a></li>

<li><a href="Chess_in_the_arts" title="Chess in the arts">Chess in the arts</a>

<ul><li><a href="Chess_in_early_literature" title="Chess in early literature">early literature</a></li>

<li>novels</li>

<li>paintings</li>

<li>poetry</li>

<li>short stories</li></ul></li>

<li><a href="List_of_chess_books" title="List of chess books">Chess books</a>

<ul><li><a href="Chess_opening_book" title="Chess opening book">opening books</a></li>

<li><a href="Chess_endgame_literature" title="Chess endgame literature">endgame literature</a></li>

<li><a href="The_Oxford_Companion_to_Chess" title="The Oxford Companion to Chess"><i>Oxford Companion</i></a></li></ul></li>

<li><a href="Chess_libraries" title="Chess libraries">Chess libraries</a></li>

<li><a href="Chess_columns_in_newspapers" title="Chess columns in newspapers">Chess newspaper columns</a></li>

<li><a href="List_of_chess_periodicals" title="List of chess periodicals">Chess periodicals</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Arbiter_(chess)" title="Arbiter (chess)">Arbiter</a></li>

<li><a href="Chess_boxing" title="Chess boxing">Chess boxing</a></li>

<li><a href="Chess_club" title="Chess club">Chess club</a></li>

<li><a href="Chess_composer" title="Chess composer">Chess composer</a></li>

<li><a href="Chess_engine" title="Chess engine">Chess engine</a>

<ul><li><a href="AlphaZero" title="AlphaZero">AlphaZero</a></li>

<li><a href="Leela_Chess_Zero" title="Leela Chess Zero">Leela Chess Zero</a></li>

<li><a href="Mittens_(chess)" title="Mittens (chess)">Mittens</a></li>

<li><a href="Stockfish_(chess)" title="Stockfish (chess)">Stockfish</a></li></ul></li>

<li><a href="Chess_problem" title="Chess problem">Chess problem</a>

<ul><li><a href="Glossary_of_chess_problems" title="Glossary of chess problems">glossary</a></li>

<li><a href="Joke_chess_problem" title="Joke chess problem">joke chess</a></li></ul></li>

<li><a href="Chess_prodigy" title="Chess prodigy">Chess prodigy</a></li>

<li><a href="Elo_rating_system" title="Elo rating system">Elo rating system</a></li>

<li><a href="Mechanical_Turk" title="Mechanical Turk">Mechanical Turk</a></li>

<li><a href="Simultaneous_exhibition" title="Simultaneous exhibition">Simultaneous exhibition</a></li>

<li><a href="Tie-breaking_in_Swiss-system_tournaments" title="Tie-breaking in Swiss-system tournaments">Tie-breaking in Swiss-system tournaments</a></li>

<li><a href="Solving_chess" title="Solving chess">Solving chess</a></li></ul>

</div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div>

<ul><li><span class="nowrap"><span class="noviewer" typeof="mw:File"></span> </span><a href="Portal%3AChess" title="Portal:Chess">Chess portal</a></li>

<li>Category</li></ul>

</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-06-09" href="https://en.wikipedia.org/wiki/?title=Chess_clock&oldid=1294649851">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

</div>

</div></div>

</div>

</main>

</div>

</body></html>