ebab7d0da53c51438720d60c6e2e467c - /page/wikibook/entry.mu

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<title>Control character</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Control character</span></span>

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</style><div role="note" class="hatnote navigation-not-searchable">"Non-printable character" redirects here. For characters in text applications, see <a href="Non-printing_character_in_word_processors" title="Non-printing character in word processors">Non-printing character in word processors</a>.</div>

<div role="note" class="hatnote navigation-not-searchable">Not to be confused with <a href="Escape_character" title="Escape character">Escape character</a>.</div>

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<p>In <a href="Computing" title="Computing">computing</a> and <a href="Telecommunications" title="Telecommunications">telecommunications</a>, a <b>control character</b> or <b>non-printing character</b> (<b>NPC</b>) is a <a href="Code_point" title="Code point">code point</a> in a <a href="Character_encoding" title="Character encoding">character set</a> that does not represent a written <a href="Character_(computing)" title="Character (computing)">character</a> or symbol. They are used as <a href="In-band_signaling" title="In-band signaling">in-band signaling</a> to cause effects other than the addition of a symbol to the text. All other characters are mainly <i><a href="Graphic_character" title="Graphic character">graphic characters</a></i>, also known as <i>printing characters</i> (or <i>printable characters</i>), except perhaps for "<a href="Space_(punctuation)" title="Space (punctuation)">space</a>" characters. In the <a href="ASCII" title="ASCII">ASCII</a> standard there are 33 control characters, such as code 7, <style data-mw-deduplicate="TemplateStyles:r886049734">

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</style><span class="monospaced">BEL</span>, which rings a terminal bell.

</p>

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

<p><a href="Prosigns_for_Morse_code" title="Prosigns for Morse code">Procedural signs</a> in <a href="Morse_code" title="Morse code">Morse code</a> are a form of control character.

</p><p>A form of control characters were introduced in the 1870 <a href="Baudot_code" title="Baudot code">Baudot code</a>: NUL and DEL.

The 1901 <a href="Murray_code" class="mw-redirect" title="Murray code">Murray code</a> added the <a href="Carriage_return" title="Carriage return">carriage return</a> (CR) and <a href="Line_feed" class="mw-redirect" title="Line feed">line feed</a> (LF), and other versions of the Baudot code included other control characters.

</p><p>The <a href="Bell_character" title="Bell character">bell character</a> (BEL), which rang a bell to alert operators, was also an early <a href="Teletype" class="mw-redirect" title="Teletype">teletype</a> control character.

</p><p>Some control characters have also been called "format effectors".

</p>

<div class="mw-heading mw-heading2"><h2 id="In_ASCII">In ASCII</h2></div>

<div role="note" class="hatnote navigation-not-searchable">Main article: <a href="C0_and_C1_control_codes#C0_controls" title="C0 and C1 control codes">C0 and C1 control codes § C0 controls</a></div>

<p>There were quite a few control characters defined (33 in ASCII, and <a href="ECMA-35" class="mw-redirect" title="ECMA-35">ECMA-35</a> adds 32 more). This was because early terminals had very primitive mechanical or electrical controls that made any kind of state-remembering <a href="API" title="API">API</a> quite expensive to implement, thus a different code for each and every function was a requirement. All entries in the <a href="ASCII" title="ASCII">ASCII</a> table below code 32<sub>10</sub> (technically the <a href="C0_and_C1_control_codes#C0_controls" title="C0 and C1 control codes">C0</a> control code set) are control characters, including <a href="Newline" title="Newline">CR and LF</a> used to separate lines of text. The code 127<sub>10</sub> (<a href="Delete_character" title="Delete character">DEL</a>) is also a control character.<sup id="cite_ref-rfc20_1-0" class="reference"><a href="#cite_note-rfc20-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><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><a href="Extended_ASCII" title="Extended ASCII">Extended ASCII</a> sets defined by ECMA-35 and <a href="ISO_8859" class="mw-redirect" title="ISO 8859">ISO 8859</a> added the codes 128<sub>10</sub> through 159<sub>10</sub> as control characters. This was primarily done so that if the <a href="Bit_numbering#Bit_significance_and_indexing" title="Bit numbering">high bit</a> was stripped, it would not change a printing character to a C0 control code. This second set is called the <a href="C0_and_C1_control_codes#C1_controls" title="C0 and C1 control codes">C1</a> set.

</p><p>IBM's <a href="EBCDIC" title="EBCDIC">EBCDIC</a> character set contains 65 control codes, including all of the ASCII C0 control codes plus additional codes which were not added to Unicode. There were also a number of attempts to define alternative sets of 32 control codes, none of these were transferred to Unicode either.

</p><p>Only a small subset of the control characters are still in use for anything resembling their original purpose:

</p>

<ul><li>0x00 (<a href="Null_character" title="Null character">null</a>, <span class="monospaced">NUL</span>, <span class="monospaced">\0</span>, <span class="monospaced">^@</span>), originally intended to be an ignored character, but now used by many <a href="Programming_language" title="Programming language">programming languages</a> including <a href="C_programming_language" class="mw-redirect" title="C programming language">C</a> to <a href="Null-terminated_string" title="Null-terminated string">mark the end of a string</a>.</li>

<li>0x04 (<a href="End-of-transmission_character" class="mw-redirect" title="End-of-transmission character">EOT</a>, <span class="monospaced">^D</span>) End Of File character on Unix terminals.<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></li>

<li>0x07 (<a href="Bell_character" title="Bell character">bell</a>, <span class="monospaced">BEL</span>, <span class="monospaced">\a</span>, <span class="monospaced">^G</span>), which may cause the device to emit a warning such as a bell or beep sound or the screen flashing.</li>

<li>0x08 (<a href="Backspace" title="Backspace">backspace</a>, <span class="monospaced">BS</span>, <span class="monospaced">\b</span>, <span class="monospaced">^H</span>), may overprint the previous character.</li>

<li>0x09 (<a href="Tab_key" title="Tab key">horizontal tab</a>, <span class="monospaced">HT</span>, <span class="monospaced">\t</span>, <span class="monospaced">^I</span>), moves the printing position right to the next tab stop.</li>

<li>0x0A (<a href="Line_feed" class="mw-redirect" title="Line feed">line feed</a>, <span class="monospaced">LF</span>, <span class="monospaced">\n</span>, <span class="monospaced">^J</span>), moves the print head down one line (and maybe to the left edge). Used as the end of line marker in Unix-like systems.</li>

<li>0x0B (<a href="Tab_key" title="Tab key">vertical tab</a>, <span class="monospaced">VT</span>, <span class="monospaced">\v</span>, <span class="monospaced">^K</span>), vertical tabulation.</li>

<li>0x0C (<a href="Page_break" title="Page break">form feed</a>, <span class="monospaced">FF</span>, <span class="monospaced">\f</span>, <span class="monospaced">^L</span>), to cause a printer to eject paper to the top of the next page, or a video terminal to clear the screen.</li>

<li>0x0D (<a href="Carriage_return" title="Carriage return">carriage return</a>, <span class="monospaced">CR</span>, <span class="monospaced">\r</span>, <span class="monospaced">^M</span>), moves the printing position to the start of the line, allowing overprinting. Used as the end of line marker in <a href="Classic_Mac_OS" title="Classic Mac OS">Classic Mac OS</a>, <a href="OS-9" title="OS-9">OS-9</a>, <a href="FLEX_(operating_system)" title="FLEX (operating system)">FLEX</a> (and variants). A <span class="monospaced">CR+LF</span> pair is used by <a href="CP/M" title="CP/M">CP/M</a>-80 and its derivatives including <a href="DOS" title="DOS">DOS</a> and <a href="Windows" class="mw-redirect" title="Windows">Windows</a>.</li>

<li>0x1B (<a href="Escape_character" title="Escape character">escape</a>, <span class="monospaced">ESC</span>, <span class="monospaced">\e</span> (<a href="GCC_(software)" class="mw-redirect" title="GCC (software)">GCC</a> only), <span class="monospaced">^[</span>). Introduces an <a href="Escape_sequence" title="Escape sequence">escape sequence</a>.</li></ul>

<p>Control characters may do something when the user inputs them, such as Ctrl+C (<a href="End-of-Text_character" title="End-of-Text character">End-of-Text character</a>, ETX) to interrupt the running process, and Ctrl+Z (<a href="Substitute_character" title="Substitute character">Substitute character</a>, SUB) for ending typed-in file on Windows. These uses usually have little to do with their ASCII definition. Modern systems often describe shortcuts as though they are control characters ("type a Ctrl+V to paste") but the code number is not even used to implement this.

</p>

<div class="mw-heading mw-heading2"><h2 id="In_Unicode">In Unicode</h2></div>

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

<p>These 65 control codes were carried over to <a href="Unicode" title="Unicode">Unicode</a>. "Control-characters" are U+0000—U+001F (C0 controls), U+007F (delete), and U+0080—U+009F (C1 controls). Their <a href="General_Category" class="mw-redirect" title="General Category">General Category</a> is "Cc". The Cc control characters have no Name in Unicode, but are given labels such as "<control-001A>" instead.<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>

</p><p>Unicode added more characters (such as the <a href="Zero-width_non-joiner" title="Zero-width non-joiner">zero-width non-joiner</a>) that could be considered controls, but it makes a distinction between these "Formatting characters" and the 65 control characters. These are General Category "Cf" instead of "Cc".

</p>

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

<p>There are a number of techniques to display non-printing characters, which may be illustrated with the <a href="Bell_character" title="Bell character">bell character</a> in <a href="ASCII" title="ASCII">ASCII</a> encoding:

</p>

<ul><li><a href="Code_point" title="Code point">Code point</a>: decimal 7, hexadecimal 0x07</li>

<li>An abbreviation, often three capital letters: BEL</li>

<li>A special character condensing the abbreviation: Unicode U+2407 (␇), "symbol for bell"</li>

<li>An <a href="ISO_2047" title="ISO 2047">ISO 2047</a> graphical representation: Unicode U+237E (⍾), "graphic for bell"</li>

<li><a href="Caret_notation" title="Caret notation">Caret notation</a> in ASCII, where code point 00xxxxx is represented as a caret followed by the capital letter at code point 10xxxxx: ^G</li>

<li>An <a href="Escape_sequence" title="Escape sequence">escape sequence</a>, as in <a href="C_(programming_language)" title="C (programming language)">C</a>/<a href="C%2B%2B" title="C++">C++</a> character string codes: <span class="monospaced">\a</span>, <span class="monospaced">\007</span>, <span class="monospaced">\x07</span>, etc.</li></ul>

<div class="mw-heading mw-heading2"><h2 id="How_control_characters_map_to_keyboards">How control characters map to keyboards</h2></div>

<p>ASCII-based <a href="Keyboard_(computing)" class="mw-redirect" title="Keyboard (computing)">keyboards</a> have a key labelled "<a href="Control_key" title="Control key">Control</a>", "Ctrl", or (rarely) "Cntl" which is used much like a shift key, being pressed in combination with another letter or symbol key. In one implementation, the control key generates the code 64 places below the code for the (generally) uppercase letter it is pressed in combination with (i.e., subtract 0x40 from ASCII code value of the (generally) uppercase letter). The other implementation is to take the ASCII code produced by the key and <a href="Bitwise_AND" class="mw-redirect" title="Bitwise AND">bitwise AND</a> it with 0x1F, forcing bits 5 to 7 to zero. For example, pressing "control" and the letter "g" (which is 0110 0111 in <a href="Binary_numeral_system" class="mw-redirect" title="Binary numeral system">binary</a>), produces the code 7 (BELL, 7 in base ten, or 0000 0111 in binary). The NULL character (code 0) is represented by Ctrl-@, "@" being the code immediately before "A" in the ASCII character set. For convenience, some terminals accept Ctrl-Space as an alias for Ctrl-@. In either case, this produces one of the 32 ASCII control codes between 0 and 31. Neither approach works to produce the DEL character because of its special location in the table and its value (code 127<sub>10</sub>), Ctrl-? is sometimes used for this character.<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><p>When the control key is held down, letter keys produce the same control characters regardless of the state of the <a href="Shift_key" title="Shift key">shift</a> or <a href="Caps_lock" class="mw-redirect" title="Caps lock">caps lock</a> keys. In other words, it does not matter whether the key would have produced an upper-case or a lower-case letter. The interpretation of the control key with the space, graphics character, and digit keys (ASCII codes 32 to 63) varies between systems. Some will produce the same character code as if the control key were not held down. Other systems translate these keys into control characters when the control key is held down. The interpretation of the control key with non-ASCII ("foreign") keys also varies between systems.

</p><p>Control characters are often rendered into a printable form known as <a href="Caret_notation" title="Caret notation">caret notation</a> by printing a caret (^) and then the ASCII character that has a value of the control character plus 64. Control characters generated using letter keys are thus displayed with the upper-case form of the letter. For example, ^G represents code 7, which is generated by pressing the G key when the control key is held down.

</p><p>Keyboards also typically have a few single keys which produce control character codes. For example, the key labelled "Backspace" typically produces code 8, "Tab" code 9, "Enter" or "Return" code 13 (though some keyboards might produce code 10 for "Enter").

</p><p>Many keyboards include keys that do not correspond to any ASCII printable or control character, for example cursor control arrows and <a href="Word_processing" class="mw-redirect" title="Word processing">word processing</a> functions. The associated keypresses are communicated to computer programs by one of four methods: appropriating otherwise unused control characters; using some encoding other than ASCII; using multi-character control sequences; or using an additional mechanism outside of generating characters. "Dumb" <a href="Computer_terminal" title="Computer terminal">computer terminals</a> typically use control sequences. Keyboards attached to stand-alone <a href="Personal_computer" title="Personal computer">personal computers</a> made in the 1980s typically use one (or both) of the first two methods. Modern computer keyboards generate <a href="Scancode" title="Scancode">scancodes</a> that identify the specific physical keys that are pressed; computer software then determines how to handle the keys that are pressed, including any of the four methods described above.

</p>

<div class="mw-heading mw-heading2"><h2 id="The_design_purpose">The design purpose</h2></div>

<p>The control characters were designed to fall into a few groups: printing and display control, data structuring, transmission control, and miscellaneous.

</p>

<div class="mw-heading mw-heading3"><h3 id="Printing_and_display_control">Printing and display control</h3></div>

<p>Printing control characters were first used to control the physical mechanism of printers, the earliest output device. An early example of this idea was the use of <a href="Baudot_code#Details" title="Baudot code">Figures (FIGS)</a> and <a href="Baudot_code#Details" title="Baudot code">Letters (LTRS)</a> in <a href="Baudot_code" title="Baudot code">Baudot code</a> to shift between two code pages. A later, but still early, example was the <a href="Out-of-band_data" title="Out-of-band data">out-of-band</a> <a href="ASA_carriage_control_characters" title="ASA carriage control characters">ASA carriage control characters</a>. Later, control characters were integrated into the stream of data to be printed.

The carriage return character (CR), when sent to such a device, causes it to put the character at the edge of the paper at which writing begins (it may, or may not, also move the printing position to the next line).

The line feed character (LF/NL) causes the device to put the printing position on the next line. It may (or may not), depending on the device and its configuration, also move the printing position to the start of the next line (which would be the leftmost position for <a href="Left-to-right" class="mw-redirect" title="Left-to-right">left-to-right</a> scripts, such as the alphabets used for Western languages, and the rightmost position for <a href="Right-to-left" class="mw-redirect" title="Right-to-left">right-to-left</a> scripts such as the Hebrew and Arabic alphabets).

The vertical and horizontal tab characters (VT and HT/TAB) cause the output device to move the printing position to the next tab stop in the direction of reading.

The form feed character (FF/NP) starts a new sheet of paper, and may or may not move to the start of the first line.

The backspace character (BS) moves the printing position one character space backwards. On printers, including <a href="Computer_terminal#Hard-copy_terminals" title="Computer terminal">hard-copy terminals</a>, this is most often used so the printer can overprint characters to make other, not normally available, characters. On <a href="Computer_terminal#VDUs" title="Computer terminal">video terminals</a> and other electronic output devices, there are often software (or hardware) configuration choices that allow a destructive backspace (e.g., a BS, SP, BS sequence), which erases, or a non-destructive one, which does not.

The shift in and shift out characters (SI and SO) selected alternate character sets, fonts, underlining, or other printing modes. Escape sequences were often used to do the same thing.

</p><p>With the advent of <a href="Computer_terminal" title="Computer terminal">computer terminals</a> that did not physically print on paper and so offered more flexibility regarding screen placement, erasure, and so forth, printing control codes were adapted. Form feeds, for example, usually cleared the screen, there being no new paper page to move to. More complex escape sequences were developed to take advantage of the flexibility of the new terminals, and indeed of newer printers. The concept of a control character had always been somewhat limiting, and was extremely so when used with new, much more flexible, hardware. Control sequences (sometimes implemented as escape sequences) could match the new flexibility and power and became the standard method. However, there were, and remain, a large variety of standard sequences to choose from.

</p>

<div class="mw-heading mw-heading3"><h3 id="Data_structuring">Data structuring</h3></div>

<p>The separators (File, Group, Record, and Unit: FS, GS, RS and US) were made to structure data, usually on a tape, in order to simulate <a href="Punched_card" title="Punched card">punched cards</a>.

End of medium (EM) warns that the tape (or other recording medium) is ending.

While many systems use CR/LF and TAB for structuring data, it is possible to encounter the separator control characters in data that needs to be structured. The separator control characters are not overloaded; there is no general use of them except to separate data into structured groupings. Their numeric values are contiguous with the space character, which can be considered a member of the group, as a word separator.

</p><p>For example, the RS separator is used by <style data-mw-deduplicate="TemplateStyles:r1238218222">

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</style><a href="RFC_(identifier)" class="mw-redirect" title="RFC (identifier)">RFC</a> <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc7464">7464</a> (JSON Text Sequences) to encode a sequence of JSON elements. Each sequence item starts with a RS character and ends with a line feed. This allows to serialize open-ended JSON sequences. It is one of the <a href="JSON_streaming" title="JSON streaming">JSON streaming</a> protocols.

</p>

<div class="mw-heading mw-heading3"><h3 id="Transmission_control">Transmission control</h3></div>

<p>The transmission control characters were intended to structure a data stream, and to manage re-transmission or graceful failure, as needed, in the face of transmission errors.

</p><p>The start of heading (SOH) character was to mark a non-data section of a data stream—the part of a stream containing addresses and other housekeeping data. The start of text character (STX) marked the end of the header, and the start of the textual part of a stream. The end of text character (ETX) marked the end of the data of a message. A widely used convention is to make the two characters preceding ETX a checksum or <a href="Cyclic_redundancy_check" title="Cyclic redundancy check">CRC</a> for error-detection purposes. The end of transmission block character (ETB) was used to indicate the end of a block of data, where data was divided into such blocks for transmission purposes.

</p><p>The escape character (<a href="Escape_character" title="Escape character">ESC</a>) was intended to "quote" the next character, if it was another control character it would print it instead of performing the control function. It is almost never used for this purpose today. Various printable characters are used as visible "<a href="Escape_character" title="Escape character">escape characters</a>", depending on context.

</p><p>The substitute character (<a href="Substitute_character" title="Substitute character">SUB</a>) was intended to request a translation of the next character from a printable character to another value, usually by setting bit 5 to zero. This is handy because some media (such as sheets of paper produced by typewriters) can transmit only printable characters. However, on MS-DOS systems with files opened in text mode, "end of text" or "end of file" is marked by this <a href="Ctrl-Z" class="mw-redirect" title="Ctrl-Z">Ctrl-Z</a> character, instead of the <a href="Ctrl-C" class="mw-redirect" title="Ctrl-C">Ctrl-C</a> or <a href="Ctrl-D" class="mw-redirect" title="Ctrl-D">Ctrl-D</a>, which are common on other operating systems.

</p><p>The cancel character (<a href="Cancel_character" title="Cancel character">CAN</a>) signaled that the previous element should be discarded. The negative acknowledge character (<a href="NAK" class="mw-redirect" title="NAK">NAK</a>) is a definite flag for, usually, noting that reception was a problem, and, often, that the current element should be sent again. The acknowledge character (<a href="Acknowledge_character" class="mw-redirect" title="Acknowledge character">ACK</a>) is normally used as a flag to indicate no problem detected with current element.

</p><p>When a transmission medium is half duplex (that is, it can transmit in only one direction at a time), there is usually a master station that can transmit at any time, and one or more slave stations that transmit when they have permission. The enquire character (<a href="Enquiry_character" title="Enquiry character">ENQ</a>) is generally used by a master station to ask a slave station to send its next message. A slave station indicates that it has completed its transmission by sending the end of transmission character (<a href="End-of-transmission_character" class="mw-redirect" title="End-of-transmission character">EOT</a>).

</p><p>The device control codes (DC1 to DC4) were originally generic, to be implemented as necessary by each device. However, a universal need in data transmission is to request the sender to stop transmitting when a receiver is temporarily unable to accept any more data. <a href="Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a> invented a convention which used 19 (the device control 3 character (<a href="Software_flow_control" title="Software flow control">DC3</a>), also known as control-S, or <a href="XOFF" class="mw-redirect" title="XOFF">XOFF</a>) to "S"top transmission, and 17 (the device control 1 character (<a href="Software_flow_control" title="Software flow control">DC1</a>), a.k.a. control-Q, or <a href="XON" class="mw-redirect" title="XON">XON</a>) to start transmission. It has become so widely used that most don't realize it is not part of official ASCII. This technique, however implemented, avoids additional wires in the data cable devoted only to transmission management, which saves money. A sensible protocol for the use of such transmission flow control signals must be used, to avoid potential deadlock conditions, however.

</p><p>The data link escape character (<a href="C0_and_C1_control_codes" title="C0 and C1 control codes">DLE</a>) was intended to be a signal to the other end of a data link that the following character is a control character such as STX or ETX. For example a packet may be structured in the following way (<a href="C0_and_C1_control_codes" title="C0 and C1 control codes">DLE</a>) <STX> <PAYLOAD> (<a href="C0_and_C1_control_codes" title="C0 and C1 control codes">DLE</a>) <ETX>.

</p>

<div class="mw-heading mw-heading3"><h3 id="Miscellaneous_codes">Miscellaneous codes</h3></div>

<p>Code 7 (<a href="Bell_character" title="Bell character">BEL</a>) is intended to cause an audible signal in the receiving terminal.<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>

</p><p>Many of the ASCII control characters were designed for devices of the time that are not often seen today. For example, code 22, "synchronous idle" (<a href="C0_and_C1_control_codes" title="C0 and C1 control codes">SYN</a>), was originally sent by synchronous modems (which have to send data constantly) when there was no actual data to send. (Modern systems typically use a start bit to announce the beginning of a transmitted word— this is a feature of <i>asynchronous</i> communication. <i>Synchronous</i> communication links were more often seen with mainframes, where they were typically run over corporate leased lines to connect a mainframe to another mainframe or perhaps a minicomputer.)

</p><p>Code 0 (ASCII code name <a href="Null_character" title="Null character">NUL</a>) is a special case. In paper tape, it is the case when there are no holes. It is convenient to treat this as a <i>fill</i> character with no meaning otherwise. Since the position of a NUL character has no holes punched, it can be replaced with any other character at a later time, so it was typically used to reserve space, either for correcting errors or for inserting information that would be available at a later time or in another place. In computing, it is often used for padding in <a href="Record-oriented_filesystem" title="Record-oriented filesystem">fixed length records</a>; to <a href="Null-terminated_string" title="Null-terminated string">mark the end of a string</a>; and formerly to <a href="Output_padding" title="Output padding">give printing devices enough time to execute a control function</a>.

</p><p>Code 127 (<a href="Delete_character" title="Delete character">DEL</a>, a.k.a. "rubout") is likewise a special case. Its 7-bit code is <i>all-bits-on</i> in binary, which essentially erased a character cell on a <a href="Paper_tape" class="mw-redirect" title="Paper tape">paper tape</a> when overpunched. Paper tape was a common storage medium when ASCII was developed, with a computing history dating back to WWII code breaking equipment at <a href="Biuro_Szyfr%C3%B3w" class="mw-redirect" title="Biuro Szyfrów">Biuro Szyfrów</a>. Paper tape became obsolete in the 1970s, so this aspect of ASCII rarely saw any use after that. Some systems (such as the original Apple computers) converted it to a backspace. But because its code is in the range occupied by other printable characters, and because it had no official assigned glyph, many computer equipment vendors used it as an additional printable character (often an all-black <a href="Box_character" class="mw-redirect" title="Box character">box character</a> useful for erasing text by overprinting with ink).

</p><p>Non-erasable <a href="Programmable_ROM" title="Programmable ROM">programmable ROMs</a> are typically implemented as arrays of fusible elements, each representing a <a href="Bit" title="Bit">bit</a>, which can only be switched one way, usually from one to zero. In such PROMs, the DEL and NUL characters can be used in the same way that they were used on punched tape: one to reserve meaningless fill bytes that can be written later, and the other to convert written bytes to meaningless fill bytes. For PROMs that switch one to zero, the roles of NUL and DEL are reversed; also, DEL will only work with 7-bit characters, which are rarely used today; for 8-bit content, the character code 255, commonly defined as a nonbreaking space character, can be used instead of DEL.

</p><p>Many <a href="File_system" title="File system">file systems</a> do not allow control characters in <a href="Filename" title="Filename">filenames</a>, as they may have reserved functions.

</p>

<ul><li><a href="Arrow_keys#HJKL_keys" title="Arrow keys">Arrow keys § HJKL keys</a>, HJKL as arrow keys, used on ADM-3A terminal</li>

<li><a href="C0_and_C1_control_codes" title="C0 and C1 control codes">C0 and C1 control codes</a></li>

<li><a href="Escape_sequence" title="Escape sequence">Escape sequence</a></li>

<li><a href="In-band_signaling" title="In-band signaling">In-band signaling</a></li>

<li><a href="Whitespace_character" title="Whitespace character">Whitespace character</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="Notes_and_references">Notes and references</h2></div>

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

<li id="cite_note-rfc20-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-rfc20_1-0">^</a></b></span> <span class="reference-text"><cite class="citation cs1"><a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc20"><i>ASCII format for network interchange</i></a>. 1969-10-01. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC0020">10.17487/RFC0020</a></span>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc20">20</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-04-05</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 book cs1">"5.2 Control Characters". <a rel="nofollow" class="external text" href="https://nvlpubs.nist.gov/nistpubs/Legacy/FIPS/fipspub1-2-1977.pdf"><i>American National Standard Code for Information Interchange | ANSI X3.4-1977</i></a> <span class="cs1-format">(PDF)</span>. National Institute for Standards. 1977. <a rel="nofollow" class="external text" href="https://ghostarchive.org/archive/20221009/https://nvlpubs.nist.gov/nistpubs/Legacy/FIPS/fipspub1-2-1977.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2022-10-09.</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 class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/2780/GA27-3005-3-2780_Data_Terminal_Description_Aug71.pdf#page=31">"EOT (End of ransmission)"</a> <span class="cs1-format">(PDF)</span>. <a rel="nofollow" class="external text" href="http://bitsavers.org/pdf/ibm/2780/GA27-3005-3-2780_Data_Terminal_Description_Aug71.pdf"><i>Component Description: IBM 2780 Data Transmission Terminal</i></a> <span class="cs1-format">(PDF)</span>. Systems Reference Library. p. 31. GA27-3005-3<span class="reference-accessdate">. Retrieved <span class="nowrap">May 21,</span> 2025</span>. <q>The EOT character terminates the current transmission and returns all terminals in the data-link to control mode. When sent by the transmitting terminal, it indicates that the terminal has nothing more to transmit and is relinquishing the communications line. The receiving terminal can send an EOT character instead of a normal DLE 0, DLE 1, or NAK response. The EOT character in this case is an abort signal that terminates the transmission. When sent in response to a polling operation, the EOT character indicates that the polled terminal has no data to transmit or is unable to continue transmission. An EOT character is recognized (except in Six- Bit Transcode) only when immediately preceded by a SYN pattern (SYN SYN EOT PAD), or when imme- diately preceded by a DLE and followed by a character of which the first four bits must be all "1" bits (PAD character) DLE EOT PAD.</q></cite></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 class="citation cs1">"4.8 Name". <a rel="nofollow" class="external text" href="https://www.unicode.org/versions/Unicode13.0.0/ch04.pdf#G2082"><i>The Unicode Standard Version 13.0 – Core Specification</i></a> <span class="cs1-format">(PDF)</span>. Unicode, Inc. <a rel="nofollow" class="external text" href="https://ghostarchive.org/archive/20221009/https://www.unicode.org/versions/Unicode13.0.0/ch04.pdf#G2082">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2022-10-09.</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 class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20091028135111/http://geocities.com/dtmcbride/tech/charsets/ascii.html">"ASCII Characters"</a>. Archived from <a rel="nofollow" class="external text" href="http://geocities.com/dtmcbride/tech/charsets/ascii.html">the original</a> on October 28, 2009<span class="reference-accessdate">. Retrieved <span class="nowrap">2010-10-08</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"><cite class="citation cs1"><a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc20"><i>ASCII format for Network Interchange</i></a>. October 1969. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC0020">10.17487/RFC0020</a></span>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc20">20</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2013-11-03</span></span>.</cite> An old RFC, which explains the structure and meaning of the control characters in chapters 4.1 and 5.2</span>

</li>

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

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

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<div class="side-box-text plainlist">Look up <i><b><a href="https://en.wiktionary.org/wiki/Appendix:Control_characters" class="extiw external" title="wiktionary:Appendix:Control characters">Appendix:Control characters</a></b></i> in Wiktionary, the free dictionary.</div></div>

</div>

<div class="side-box-text plainlist">Look up <i><b><a href="https://en.wiktionary.org/wiki/Control_character" class="extiw external" title="wiktionary:Control character">Control character</a></b></i> or <i><b><a href="https://en.wiktionary.org/wiki/Control_code" class="extiw external" title="wiktionary:Control code">Control code</a></b></i> in Wiktionary, the free dictionary.</div></div>

</div>

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</style><div id="Character_encodings589" style="font-size:114%;margin:0 4em"><a href="Character_encoding" title="Character encoding">Character encodings</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Early telecommunications</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Telegraph_code" title="Telegraph code">Telegraph code</a>

<ul><li><a href="Cooke_and_Wheatstone_telegraph#Codes" title="Cooke and Wheatstone telegraph">Needle</a></li>

<li><a href="Morse_code" title="Morse code">Morse</a>

<ul><li><a href="Morse_code_for_non-Latin_alphabets" title="Morse code for non-Latin alphabets">Non-Latin</a></li>

<li><a href="Wabun_code" title="Wabun code">Wabun/Kana</a></li>

<li><a href="Chinese_telegraph_code" title="Chinese telegraph code">Chinese</a></li>

<li><a href="Russian_Morse_code" title="Russian Morse code">Cyrillic</a></li></ul></li>

<li><a href="Baudot_code" title="Baudot code">Baudot and Murray</a></li></ul></li>

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

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

<li><a href="BCD_(character_encoding)" title="BCD (character encoding)">BCDIC</a></li>

<li><a href="Teletex" title="Teletex">Teletex</a> and <a href="Videotex" title="Videotex">Videotex</a>/<a href="Teletext" title="Teletext">Teletext</a>

<li>World System Teletext

<ul><li><a href="World_System_Teletext" title="World System Teletext">background</a></li>

<li><a href="Transcode_(character_encoding)" title="Transcode (character encoding)">Transcode</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="ISO/IEC_8859" title="ISO/IEC 8859">ISO/IEC 8859</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li>Approved parts

<ul><li><a href="ISO/IEC_8859-1" title="ISO/IEC 8859-1">-1 (Western Europe)</a></li>

<li><a href="ISO/IEC_8859-2" title="ISO/IEC 8859-2">-2 (Central Europe)</a></li>

<li><a href="ISO/IEC_8859-3" title="ISO/IEC 8859-3">-3 (Maltese/Esperanto)</a></li>

<li><a href="ISO/IEC_8859-4" title="ISO/IEC 8859-4">-4 (North Europe)</a></li>

<li><a href="ISO/IEC_8859-5" title="ISO/IEC 8859-5">-5 (Cyrillic)</a></li>

<li><a href="ISO/IEC_8859-6" title="ISO/IEC 8859-6">-6 (Arabic)</a></li>

<li><a href="ISO/IEC_8859-7" title="ISO/IEC 8859-7">-7 (Greek)</a></li>

<li><a href="ISO/IEC_8859-8" title="ISO/IEC 8859-8">-8 (Hebrew)</a></li>

<li><a href="ISO/IEC_8859-9" title="ISO/IEC 8859-9">-9 (Turkish)</a></li>

<li><a href="ISO/IEC_8859-10" title="ISO/IEC 8859-10">-10 (Nordic)</a></li>

<li><a href="ISO/IEC_8859-13" title="ISO/IEC 8859-13">-13 (Baltic)</a></li>

<li><a href="ISO/IEC_8859-14" title="ISO/IEC 8859-14">-14 (Celtic)</a></li>

<li><a href="ISO/IEC_8859-15" title="ISO/IEC 8859-15">-15 (New Western Europe)</a></li>

<li><a href="ISO/IEC_8859-16" title="ISO/IEC 8859-16">-16 (Romanian)</a></li></ul></li>

<li>Abandoned parts

<ul><li><a href="ISO/IEC_8859-12" class="mw-redirect" title="ISO/IEC 8859-12">-12 (Devanagari)</a></li></ul></li>

<li>Proposed but not approved

<ul><li><a href="ISO-IR-111" title="ISO-IR-111">KOI-8 Cyrillic</a></li>

<li>Adaptations

<ul><li><a href="ISO-IR-182" title="ISO-IR-182">Welsh</a></li>

<li><a href="Code_page_922" title="Code page 922">Estonian</a></li>

<li><a href="Code_page_1124" title="Code page 1124">Ukrainian Cyrillic</a></li></ul></li></ul>

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

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

<li><a href="Chinese_Character_Code_for_Information_Interchange" title="Chinese Character Code for Information Interchange">CCCII/EACC</a></li></ul></li>

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

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

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

<li><a href="BSCII" class="mw-redirect" title="BSCII">BSCII</a></li>

<li><a href="Hong_Kong_Supplementary_Character_Set" title="Hong Kong Supplementary Character Set">HKSCS</a></li>

<li><a href="Indian_Script_Code_for_Information_Interchange" title="Indian Script Code for Information Interchange">ISCII</a></li>

<li><a href="Perso-Arabic_Script_Code_for_Information_Interchange" title="Perso-Arabic Script Code for Information Interchange">PASCII</a></li>

<li><a href="Shift_JIS" title="Shift JIS">Shift JIS</a></li>

<li><a href="Tamil_Script_Code_for_Information_Interchange" title="Tamil Script Code for Information Interchange">TSCII</a></li>

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

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

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

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="ISO/IEC_2022" title="ISO/IEC 2022">ISO/IEC 2022</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Extended_Unix_Code" title="Extended Unix Code">Extended Unix Code / EUC</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Mac OS <a href="Code_page" title="Code page">Code pages</a><br>("scripts")</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Mac_OS_Armenian" title="Mac OS Armenian">Armenian</a></li>

<li><a href="MacArabic_encoding" title="MacArabic encoding">Arabic</a></li>

<li><a href="Mac_OS_Barents_Cyrillic" title="Mac OS Barents Cyrillic">Barents Cyrillic</a></li>

<li><a href="Mac_OS_Celtic" title="Mac OS Celtic">Celtic</a></li>

<li><a href="Mac_OS_Central_European_encoding" title="Mac OS Central European encoding">Central European</a></li>

<li><a href="Mac_OS_Croatian_encoding" title="Mac OS Croatian encoding">Croatian</a></li>

<li><a href="Mac_OS_Cyrillic_encoding" title="Mac OS Cyrillic encoding">Cyrillic</a></li>

<li><a href="Mac_OS_Devanagari_encoding" title="Mac OS Devanagari encoding">Devanagari</a></li>

<li><a href="MacFarsi_encoding" title="MacFarsi encoding">Farsi (Persian)</a></li>

<li><a href="Macintosh_Font_X_encoding" title="Macintosh Font X encoding">Font X (Kermit)</a></li>

<li><a href="Mac_OS_Gaelic" title="Mac OS Gaelic">Gaelic</a></li>

<li><a href="Mac_OS_Georgian" title="Mac OS Georgian">Georgian</a></li>

<li><a href="Mac_OS_Greek_encoding" title="Mac OS Greek encoding">Greek</a></li>

<li><a href="Mac_OS_Gujarati" title="Mac OS Gujarati">Gujarati</a></li>

<li><a href="Mac_OS_Gurmukhi" title="Mac OS Gurmukhi">Gurmukhi</a></li>

<li><a href="Mac_OS_Hebrew" title="Mac OS Hebrew">Hebrew</a></li>

<li><a href="Mac_OS_Icelandic_encoding" title="Mac OS Icelandic encoding">Iceland</a></li>

<li><a href="Mac_OS_Inuit" title="Mac OS Inuit">Inuit</a></li>

<li><a href="Mac_OS_Keyboard_encoding" title="Mac OS Keyboard encoding">Keyboard</a></li>

<li><a href="Macintosh_Latin_encoding" title="Macintosh Latin encoding">Latin (Kermit)</a></li>

<li><a href="Mac_OS_Maltese/Esperanto_encoding" title="Mac OS Maltese/Esperanto encoding">Maltese/Esperanto</a></li>

<li><a href="Mac_OS_Ogham" title="Mac OS Ogham">Ogham</a></li>

<li><a href="Mac_OS_Roman" title="Mac OS Roman">Roman</a></li>

<li><a href="Mac_OS_Romanian_encoding" title="Mac OS Romanian encoding">Romanian</a></li>

<li><a href="Mac_OS_Turkish_encoding" title="Mac OS Turkish encoding">Turkish</a></li>

<li><a href="Mac_OS_Turkic_Cyrillic" title="Mac OS Turkic Cyrillic">Turkic Cyrillic</a></li>

<li><a href="Mac_OS_Ukrainian_encoding" title="Mac OS Ukrainian encoding">Ukrainian</a></li>

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

<li><a href="ABICOMP_character_set" title="ABICOMP character set">ABICOMP</a></li>

<li><a href="CS_Indic_character_set" title="CS Indic character set">CS Indic</a></li>

<li><a href="CSX_Indic_character_set" title="CSX Indic character set">CSX Indic</a></li>

<li><a href="CSX%2B_Indic_character_set" title="CSX+ Indic character set">CSX+ Indic</a></li>

<li><a href="Iran_System_encoding" title="Iran System encoding">Iran System</a></li>

<li><a href="Kamenick%C3%BD_encoding" title="Kamenický encoding">Kamenický</a></li>

<li><a href="Mazovia_encoding" title="Mazovia encoding">Mazovia</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="IBM_AIX" title="IBM AIX">IBM AIX code pages</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Windows_code_page" title="Windows code page">Windows code pages</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Extended_Latin-8" title="Extended Latin-8">Extended Latin-8</a></li>

<li><a href="Windows_Cyrillic_%2B_French" title="Windows Cyrillic + French">Cyrillic + French</a></li>

<li><a href="Windows_Cyrillic_%2B_German" title="Windows Cyrillic + German">Cyrillic + German</a></li>

<li><a href="Windows_Polytonic_Greek" title="Windows Polytonic Greek">Polytonic Greek</a></li></ul>

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

<ul><li><a href="Japanese_language_in_EBCDIC" title="Japanese language in EBCDIC">Japanese language in EBCDIC</a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Digital_Equipment_Corporation" title="Digital Equipment Corporation">DEC</a> terminals (<a href="VT220" title="VT220">VTx</a>)</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Multinational_Character_Set" title="Multinational Character Set">Multinational (MCS)</a></li>

<li><a href="National_Replacement_Character_Set" title="National Replacement Character Set">National Replacement (NRCS)</a>

<ul><li><a href="Code_page_1020" title="Code page 1020">French Canadian</a></li>

<li><a href="Code_page_1021" title="Code page 1021">Swiss</a></li>

<li><a href="Code_page_1023" title="Code page 1023">Spanish</a></li>

<li><a href="Code_page_1101" title="Code page 1101">United Kingdom</a></li>

<li><a href="Code_page_1102" title="Code page 1102">Dutch</a></li>

<li><a href="Code_page_1103" title="Code page 1103">Finnish</a></li>

<li><a href="Code_page_1104" title="Code page 1104">French</a></li>

<li><a href="Code_page_1105" title="Code page 1105">Norwegian and Danish</a></li>

<li><a href="Code_page_1106" title="Code page 1106">Swedish</a></li>

<li><a href="Code_page_1107" title="Code page 1107">Norwegian and Danish (alternative)</a></li></ul></li>

<li><a href="Code_page_1287" title="Code page 1287">8-bit Greek</a></li>

<li><a href="Code_page_1288" title="Code page 1288">8-bit Turkish</a></li>

<li><a href="DEC_Hebrew" title="DEC Hebrew">Hebrew</a></li>

<li><a href="DEC_Special_Graphics" title="DEC Special Graphics">Special Graphics</a></li>

<li><a href="DEC_Technical_Character_Set" title="DEC Technical Character Set">Technical (TCS)</a></li></ul>

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

<li><a href="RISC_OS_character_set" title="RISC OS character set">Acorn RISC OS</a></li>

<li><a href="Amstrad_CPC_character_set" title="Amstrad CPC character set">Amstrad CPC</a></li>

<li><a href="Apple_II_character_set" title="Apple II character set">Apple II</a></li>

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

<li><a href="Atari_ST_character_set" title="Atari ST character set">Atari ST</a></li>

<li><a href="Casio_calculator_character_sets" title="Casio calculator character sets">Casio calculators</a></li>

<li><a href="Intecolor/Compucolor_8001_character_set" class="mw-redirect" title="Intecolor/Compucolor 8001 character set">Compucolor 8001</a></li>

<li><a href="Compucolor_II_character_set" title="Compucolor II character set">Compucolor II</a></li>

<li><a href="DEC_RADIX_50" title="DEC RADIX 50">DEC RADIX 50</a></li>

<li><a href="DG_International" title="DG International">DG International</a></li>

<li><a href="Galaksija_(computer)#Character_ROM" title="Galaksija (computer)">Galaksija</a></li>

<li><a href="HP_Roman" title="HP Roman">HP Roman</a></li>

<li><a href="FOCAL_character_set" title="FOCAL character set">HP FOCAL</a></li>

<li><a href="SQUOZE#Identifier_name_character_encoding" title="SQUOZE">SQUOZE</a></li>

<li><a href="Lotus_Multi-Byte_Character_Set" title="Lotus Multi-Byte Character Set">LMBCS</a></li>

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

<li><a href="PostScript_Standard_Encoding" title="PostScript Standard Encoding">PostScript Standard</a></li>

<li><a href="PostScript_Latin_1_Encoding" title="PostScript Latin 1 Encoding">PostScript Latin 1</a></li>

<li><a href="SAM_Coup%C3%A9_character_set" class="mw-redirect" title="SAM Coupé character set">SAM Coupé</a></li>

<li><a href="Sharp_pocket_computer_character_sets" title="Sharp pocket computer character sets">Sharp calculators</a></li>

<li><a href="Sharp_MZ_character_set" title="Sharp MZ character set">Sharp MZ</a></li>

<li><a href="Sinclair_QL_character_set" title="Sinclair QL character set">Sinclair QL</a></li>

<li><a href="Teletext_character_set" title="Teletext character set">Teletext</a></li>

<li><a href="TI_calculator_character_sets" title="TI calculator character sets">TI calculators</a></li>

<li><a href="Ventura_International" title="Ventura International">Ventura International</a></li>

<li><a href="Wang_International_Standard_Code_for_Information_Interchange" title="Wang International Standard Code for Information Interchange">WISCII</a></li>

<li><a href="ZX_Spectrum_character_set" title="ZX Spectrum character set">ZX Spectrum</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Unicode" title="Unicode">Unicode</a> / <a href="Universal_Coded_Character_Set" title="Universal Coded Character Set">ISO/IEC 10646</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="UTF-EBCDIC" title="UTF-EBCDIC">UTF-EBCDIC</a></li>

<li><a href="Comparison_of_Unicode_encodings" title="Comparison of Unicode encodings">Comparison of Unicode encodings</a></li></ul>

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

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

<ul><li><a href="ABICOMP_character_set" title="ABICOMP character set">ABICOMP</a></li>

<li><a href="Digital_encoding_of_APL_symbols" title="Digital encoding of APL symbols">Digital encoding of APL symbols</a>

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

<li>INIS

<li><i><a href="Mojiky%C5%8D" title="Mojikyō">Mojikyō</a></i></li>

<li><a href="Stanford_Extended_ASCII" title="Stanford Extended ASCII">SEASCII</a></li>

<li><a href="Stanford/ITS_character_set" title="Stanford/ITS character set">Stanford/ITS</a></li>

<li><a href="Symbol_(typeface)" title="Symbol (typeface)">Symbol</a></li>

<li><a href="Unified_Hangul_Code" title="Unified Hangul Code">Unified Hangul Code</a></li></ul>

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

<ul><li><a href="Prosigns_for_Morse_code" title="Prosigns for Morse code">Morse prosigns</a></li>

<li><a href="C0_and_C1_control_codes" title="C0 and C1 control codes">C0 and C1 control codes</a>

<li><a href="Unicode_control_characters" title="Unicode control characters">Unicode control, format and separator characters</a></li>

<li><a href="Whitespace_character" title="Whitespace character">Whitespace characters</a></li></ul>

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

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

<li><a href="Character_encodings_in_HTML" title="Character encodings in HTML">Character encodings in HTML</a></li>

<li><a href="Charset_detection" title="Charset detection">Charset detection</a></li>

<li><a href="Han_unification" title="Han unification">Han unification</a></li>

<li><a href="Hardware_code_page" title="Hardware code page">Hardware code page</a></li>

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

<li><a href="Variable-width_encoding" title="Variable-width encoding">Variable-length encoding</a></li></ul>

</div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><span class="noviewer" typeof="mw:File"><span title="Category"></span></span> Character sets</div></td></tr></tbody></table></div>

<div class="navbox-styles"></div><div role="navigation" class="navbox authority-control" aria-label="Navbox390" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Authority control databases: National </th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://d-nb.info/gnd/4555289-7">Germany</a></span></li></ul></div></td></tr></tbody></table></div></div><div><div class="zim-footer">

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