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<title>Variable-width encoding</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Variable-width encoding</span></span>

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</style><div role="note" class="hatnote navigation-not-searchable">This article is about the storage of text in computers. For the transmission of data across noisy channels, see <a href="Variable-length_code" title="Variable-length code">variable-length code</a>.</div>

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A <b>variable-width encoding</b> is a type of <a href="Character_encoding" title="Character encoding">character encoding</a> scheme in which codes of differing lengths are used to encode a <a href="Character_set" class="mw-redirect" title="Character set">character set</a> (a repertoire of symbols) for representation, usually in a <a href="Computer" title="Computer">computer</a>.<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><sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>a<span class="cite-bracket">]</span></a></sup> Most common variable-width encodings are <b>multibyte encodings</b> (aka <b>MBCS</b> – <b>multi-byte character set</b>), which use varying numbers of <a href="Byte" title="Byte">bytes</a> (<a href="Octet_(computing)" title="Octet (computing)">octets</a>) to encode different characters. (Some authors, notably in <a href="Microsoft" title="Microsoft">Microsoft</a> documentation, use the term <i>multibyte character set,</i> which is a <a href="Misnomer" title="Misnomer">misnomer</a>, because representation size is an attribute of the encoding, not of the character set.)

</p><p>Early variable-width encodings using less than a byte per character were sometimes used to pack English text into fewer bytes in <a href="Adventure_game" title="Adventure game">adventure games</a> for early <a href="Microcomputer" title="Microcomputer">microcomputers</a>. However <a href="Disk_storage" title="Disk storage">disks</a> (which unlike tapes allowed random access allowing text to be loaded on demand), increases in computer memory and general purpose <a href="Compression_algorithm" class="mw-redirect" title="Compression algorithm">compression algorithms</a> have rendered such tricks largely obsolete.

</p><p>Multibyte encodings are usually the result of a need to increase the number of characters which can be encoded without breaking <a href="Backward_compatibility" title="Backward compatibility">backward compatibility</a> with an existing constraint. For example, with one byte (8 bits) per character, one can encode 256 possible characters; in order to encode more than 256 characters, the obvious choice would be to use two or more bytes per encoding unit, two bytes (16 bits) would allow 65,536 possible characters, but such a change would break compatibility with existing systems and therefore might not be feasible at all.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>b<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="General_structure">General structure</h2></div>

<p>Since the aim of a multibyte encoding system is to minimise changes to existing application software, some characters must retain their pre-existing single-unit codes, even while other characters have multiple units in their codes. The result is that there are three sorts of units in a variable-width encoding: <b>singletons</b>, which consist of a single unit, <b>lead units</b>, which come first in a multiunit sequence, and <b>trail units</b>, which come afterwards in a multiunit sequence. Input and display software obviously needs to know about the structure of the multibyte encoding scheme, but other software generally doesn't need to know if a pair of bytes represent two separate characters or just one character.

</p><p>For example, the four character string "<a href="I_Love_New_York" title="I Love New York">I♥NY</a>" is encoded in <a href="UTF-8" title="UTF-8">UTF-8</a> like this (shown as <a href="Hexadecimal" title="Hexadecimal">hexadecimal</a> byte values): <style data-mw-deduplicate="TemplateStyles:r886049734">

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</style><span class="monospaced">49 <span style="color: Maroon;">E2</span> <span style="color:navy">99</span> <span style="color:navy">A5</span> 4E 59</span>. Of the six units in that sequence, 49, 4E, and 59 are singletons (for <i>I, N,</i> and <i>Y</i>), <span style="color: Maroon;">E2</span> is a lead unit and <span style="color:navy">99</span> and <span style="color:navy">A5</span> are trail units. The heart symbol is represented by the combination of the lead unit and the two trail units.

</p><p>UTF-8 makes it easy for a program to identify the three sorts of units, since they fall into separate value ranges. Older variable-width encodings are typically not as well-designed, since the ranges may overlap. A text processing application that deals with the variable-width encoding must then scan the text from the beginning of all definitive sequences in order to identify the various units and interpret the text correctly. In such encodings, one is liable to encounter false positives when searching for a string in the middle of the text. For example, if the hexadecimal values DE, DF, E0, and E1 can all be either lead units or trail units, then a search for the two-unit sequence DF E0 can yield a false positive in the sequence DE DF E0 E1, which consists of two consecutive two-unit sequences. There is also the danger that a single corrupted or lost unit may render the whole interpretation of a large run of multiunit sequences incorrect. In a variable-width encoding where all three types of units are disjunct, string searching always works without false positives, and (provided the decoder is well written) the corruption or loss of one unit corrupts only one character.

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<div class="mw-heading mw-heading2"><h2 id="CJK_multibyte_encodings">CJK multibyte encodings</h2></div>

<p>The first use of multibyte encodings was for the encoding of Chinese, Japanese and Korean, which have large character sets well in excess of 256 characters. At first the encoding was constrained to the limit of 7 bits. The <a href="ISO/IEC_2022" title="ISO/IEC 2022">ISO-2022-JP, ISO-2022-CN and ISO-2022-KR encodings</a> used the range 21–7E (hexadecimal) for both lead units and trail units, and marked them off from the singletons by using ISO 2022 escape sequences to switch between single-byte and multibyte mode. A total of 8,836 (94×94) characters could be encoded at first, and further sets of 94×94 characters with switching. The ISO 2022 encoding schemes for CJK are still in use on the Internet. The stateful nature of these encodings and the large overlap make them very awkward to process.

</p><p>On <a href="Unix" title="Unix">Unix</a> platforms, the ISO 2022 7-bit encodings were replaced by a set of 8-bit encoding schemes, the Extended Unix Code: EUC-JP, EUC-CN and EUC-KR. Instead of distinguishing between the multiunit sequences and the singletons with escape sequences, which made the encodings stateful, multiunit sequences were marked by having the most significant bit set, that is, being in the range 80–FF (hexadecimal), while the singletons were in the range 00–7F alone. The lead units and trail units were in the range A1 to FE (hexadecimal), that is, the same as their range in the ISO 2022 encodings, but with the high bit set to 1. These encodings were reasonably easy to work with provided all your delimiters were <a href="ASCII" title="ASCII">ASCII</a> characters and you avoided truncating strings to fixed lengths, but a break in the middle of a multibyte character could still cause major corruption.

</p><p>On the PC (<a href="DOS" title="DOS">DOS</a> and <a href="Microsoft_Windows" title="Microsoft Windows">Microsoft Windows</a> platforms), two encodings became established for Japanese and Traditional Chinese in which all of singletons, lead units and trail units overlapped: <a href="Shift-JIS" class="mw-redirect" title="Shift-JIS">Shift-JIS</a> and <a href="Big5" title="Big5">Big5</a> respectively. In Shift-JIS, lead units had the range 81–9F and E0–FC, trail units had the range 40–7E and 80–FC, and singletons had the range 21–7E and A1–DF. In Big5, lead units had the range A1–FE, trail units had the range 40–7E and A1–FE, and singletons had the range 21–7E (all values in hexadecimal). This overlap again made processing tricky, though at least most of the symbols had unique byte values (though strangely the backslash does not).

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<div class="mw-heading mw-heading2"><h2 id="Unicode_variable-width_encodings">Unicode variable-width encodings</h2></div>

<p>The <a href="Unicode" title="Unicode">Unicode</a> standard has two variable-width encodings: <a href="UTF-8" title="UTF-8">UTF-8</a> and <a href="UTF-16" title="UTF-16">UTF-16</a> (it also has a fixed-width encoding, <a href="UTF-32" title="UTF-32">UTF-32</a>). Originally, both the Unicode and <a href="ISO_10646" class="mw-redirect" title="ISO 10646">ISO 10646</a> standards were meant to be fixed-width, with Unicode being 16-bit and ISO 10646 being 32-bit. ISO 10646 provided a variable-width encoding called <a href="UTF-1" title="UTF-1">UTF-1</a>, in which singletons had the range 00–9F, lead units the range A0–FF and trail units the ranges A0–FF and 21–7E. Because of this bad design, similar to <a href="Shift_JIS" title="Shift JIS">Shift JIS</a> and <a href="Big5" title="Big5">Big5</a> in its overlap of values, the inventors of the <a href="Plan_9_from_Bell_Labs" title="Plan 9 from Bell Labs">Plan 9</a> operating system, the first to implement Unicode throughout, abandoned it and replaced it with a much better designed variable-width encoding for Unicode: UTF-8, in which singletons have the range 00–7F, lead units have the range C0–FD (now actually C2–F4, to avoid overlong sequences and to maintain synchronism with the encoding capacity of UTF-16; see the <a href="UTF-8" title="UTF-8">UTF-8</a> article), and trail units have the range 80–BF. The lead unit also tells how many trail units follow: one after C2–DF, two after E0–EF and three after F0–F4.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>c<span class="cite-bracket">]</span></a></sup>

</p><p>UTF-16 was devised to break free of the 65,536-character limit of the original Unicode (1.x) without breaking compatibility with the 16-bit encoding. In UTF-16, singletons have the range 0000–D7FF (55,296 code points) and E000–FFFF (8192 code points, 63,488 in total), lead units the range D800–DBFF (1024 code points) and trail units the range DC00–DFFF (1024 code points, 2048 in total). The lead and trail units, called <i>high surrogates</i> and <i>low surrogates</i>, respectively, in Unicode terminology, map 1024×1024 or 1,048,576 supplementary characters, making 1,112,064 (63,488 BMP code points + 1,048,576 code points represented by high and low surrogate pairs) encodable code points, or <i>scalar values</i> in Unicode parlance (surrogates are not encodable).

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<ul><li><a href="Wchar_t" class="mw-redirect" title="Wchar t">wchar_t</a> wide characters</li>

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

<li><a href="Triple-Byte_Character_Set" class="mw-redirect" title="Triple-Byte Character Set">Triple-Byte Character Set</a> (TBCS)</li>

<li><a href="Double-byte_character_set" title="Double-byte character set">Double-Byte Character Set</a> (DBCS)</li>

<li><a href="SBCS" title="SBCS">Single-Byte Character Set</a> (SBCS)</li></ul>

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

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<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text">The concept long precedes the advent of the electronic computer, however, as seen with <a href="Morse_code" title="Morse code">Morse code</a>.</span>

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<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text">As a real-life example of this, <a href="UTF-16" title="UTF-16">UTF-16</a>, which represents the most common characters in exactly the manner just described (and uses pairs of 16-bit code units for less-common characters) never gained traction as an encoding for text intended for interchange due to its incompatibility with the ubiquitous 7-/8-bit <a href="ASCII" title="ASCII">ASCII</a> encoding, with its intended role instead being taken by <a href="UTF-8" title="UTF-8">UTF-8</a>, which <i>does</i> preserve ASCII compatibility.</span>

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<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text">In the original version of UTF-8, from its 1992 publication until its code space was restricted to that of UTF-16 in 2003, the range of lead units encoding three-unit trailing sequences was larger (F0–F7); additionally, the lead units F8–FB were followed by four trail units, and FC–FD by five. FE–FF were never valid lead or trail units in any version of UTF-8.</span>

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

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</style><cite id="CITEREFCrispin2005" class="citation cs1">Crispin, M. (1 April 2005). <i>UTF-9 and UTF-18 Efficient Transformation Formats of Unicode</i>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2Frfc4042">10.17487/rfc4042</a>.</cite></span>

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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%"><a href="Control_character" title="Control character">Control character</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><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>

</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><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-02-14" href="https://en.wikipedia.org/wiki/?title=Variable-width_encoding&oldid=1275750192">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.

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