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Variable-width Encoding
A variable-width encoding is a type of character encoding scheme in which codes of differing lengths are used to encode a character set (a repertoire of symbols) for representation, usually in a computer. Most common variable-width encodings are multibyte encodings (aka MBCS – multi-byte character set), which use varying numbers of bytes (octets) to encode different characters. (Some authors, notably in Microsoft documentation, use the term ''multibyte character set,'' which is a misnomer, because representation size is an attribute of the encoding, not of the character set.) Early variable-width encodings using less than a byte per character were sometimes used to pack English text into fewer bytes in adventure games for early microcomputers. However disks (which unlike tapes allowed random access allowing text to be loaded on demand), increases in computer memory and general purpose compression algorithms have rendered such tricks largely obsolete. Multibyte encodings are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Character Encoding
Character encoding is the process of assigning numbers to graphical character (computing), characters, especially the written characters of human language, allowing them to be stored, transmitted, and transformed using computers. The numerical values that make up a character encoding are known as code points and collectively comprise a code space or a code page. Early character encodings that originated with optical or electrical telegraphy and in early computers could only represent a subset of the characters used in written languages, sometimes restricted to Letter case, upper case letters, Numeral system, numerals and some punctuation only. Over time, character encodings capable of representing more characters were created, such as ASCII, the ISO/IEC 8859 encodings, various computer vendor encodings, and Unicode encodings such as UTF-8 and UTF-16. The Popularity of text encodings, most popular character encoding on the World Wide Web is UTF-8, which is used in 98.2% of surve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexadecimal
Hexadecimal (also known as base-16 or simply hex) is a Numeral system#Positional systems in detail, positional numeral system that represents numbers using a radix (base) of sixteen. Unlike the decimal system representing numbers using ten symbols, hexadecimal uses sixteen distinct symbols, most often the symbols "0"–"9" to represent values 0 to 9 and "A"–"F" to represent values from ten to fifteen. Software developers and system designers widely use hexadecimal numbers because they provide a convenient representation of binary code, binary-coded values. Each hexadecimal digit represents four bits (binary digits), also known as a nibble (or nybble). For example, an 8-bit byte is two hexadecimal digits and its value can be written as to in hexadecimal. In mathematics, a subscript is typically used to specify the base. For example, the decimal value would be expressed in hexadecimal as . In programming, several notations denote hexadecimal numbers, usually involving a prefi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lotus Multi-Byte Character Set
The Lotus Multi-Byte Character Set (LMBCS) is a proprietary multi-byte character encoding originally conceived in 1988 at Lotus Development Corporation with input from Bob Balaban and others. Created around the same time and addressing some of the same problems, LMBCS could be viewed as parallel development and possible alternative to Unicode. For maximum compatibility, later issues of LMBCS incorporate UTF-16 as a subset. Commercially, LMBCS was first introduced as the default character set of Lotus 1-2-3 Release 3 for DOS in March 1989 and Lotus 1-2-3/G Release 1 for OS/2 in 1990 replacing the 8-bit Lotus International Character Set (LICS) and ASCII used in earlier DOS-only versions of Lotus 1-2-3 and Symphony. LMBCS is also used in IBM/ Lotus SmartSuite, Notes and Domino, as well as in a number of third-party products. LMBCS encodes the characters required for languages using the Latin, Arabic, Hebrew, Greek and Cyrillic scripts, the Thai, Chinese, Japanese and Korean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wchar T
The C programming language has a set of functions implementing operations on strings (character strings and byte strings) in its standard library. Various operations, such as copying, concatenation, tokenization and searching are supported. For character strings, the standard library uses the convention that strings are null-terminated: a string of characters is represented as an array of elements, the last of which is a " character" with numeric value 0. The only support for strings in the programming language proper is that the compiler translates quoted string constants into null-terminated strings. Definitions A string is defined as a contiguous sequence of code units terminated by the first zero code unit (often called the ''NUL'' code unit). This means a string cannot contain the zero code unit, as the first one seen marks the end of the string. The ''length'' of a string is the number of code units before the zero code unit. The memory occupied by a string is alwa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plan 9 From Bell Labs
Plan 9 from Bell Labs is a distributed operating system which originated from the Computing Science Research Center (CSRC) at Bell Labs in the mid-1980s and built on UNIX concepts first developed there in the late 1960s. Since 2000, Plan 9 has been free and open-source. The final official release was in early 2015. Under Plan 9, UNIX's '' everything is a file'' metaphor is extended via a pervasive network-centric filesystem, and the cursor-addressed, terminal-based I/O at the heart of UNIX-like operating systems is replaced by a windowing system and graphical user interface without cursor addressing, although rc, the Plan 9 shell, is text-based. The name ''Plan 9 from Bell Labs'' is a reference to the Ed Wood 1957 cult science fiction Z-movie '' Plan 9 from Outer Space''. The system continues to be used and developed by operating system researchers and hobbyists. History Plan 9 from Bell Labs was originally developed, starting in the late 1980s, by members of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shift JIS
Shift JIS (also SJIS, MIME name Shift_JIS, known as PCK in Solaris contexts) is a character encoding for the Japanese language, originally developed by the Japanese company ASCII Corporation in conjunction with Microsoft and standardized as JIS X 0208 Appendix 1. Shift JIS is based on character sets defined within JIS standards (for the single-byte characters) and (for the double-byte characters). , less than 0.05% of surveyed web pages used Shift JIS (actually decoded as its superset Windows-31J encoding), a decline from 1.3% in July 2014. Shift JIS is the third-most declared character encoding for Japanese websites (though in effect it means its superset Windows-31J is used, so it is third-most popular), declared by 1.0% of sites in the .jp domain, while UTF-8 is used by 99% of Japanese websites. Shift JIS is also sometimes used in QR codes (they are a Japanese invention also allowing UTF-8, which may though be preferred use). Structure Shift JIS is an extension ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UTF-1
UTF-1 is an obsolete method of transforming ISO/IEC 10646/Unicode into a stream of bytes. Its design does not provide self-synchronization, which makes searching for substrings and error recovery difficult. It reuses the ASCII printing characters for multi-byte encodings, making it unsuited for some uses (for instance Unix filenames cannot contain the byte value used for forward slash). UTF-1 is also slow to encode or decode due to its use of division and multiplication by a number which is not a power of 2. Due to these issues, it did not gain acceptance and was quickly replaced by UTF-8. Design Similar to UTF-8, UTF-1 is a variable-width encoding that is backwards-compatible with ASCII. Every Unicode code point is represented by either a single byte, or a sequence of two, three, or ''five'' bytes. All ASCII code points are a single byte (the code points through are also single bytes). UTF-1 does not use the C0 and C1 control codes or the space character in multi-byte en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO 10646
The International Organization for Standardization (ISO ; ; ) is an independent, non-governmental, international standard development organization composed of representatives from the national standards organizations of member countries. Membership requirements are given in Article 3 of the ISO Statutes. ISO was founded on 23 February 1947, and () it has published over 25,000 international standards covering almost all aspects of technology and manufacturing. It has over 800 technical committees (TCs) and subcommittees (SCs) to take care of standards development. The organization develops and publishes international standards in technical and nontechnical fields, including everything from manufactured products and technology to food safety, transport, IT, agriculture, and healthcare. More specialized topics like electrical and electronic engineering are instead handled by the International Electrotechnical Commission.Editors of Encyclopedia Britannica. 3 June 2021.Internatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UTF-32
UTF-32 (32- bit Unicode Transformation Format), sometimes called UCS-4, is a fixed-length encoding used to encode Unicode code points that uses exactly 32 bits (four bytes) per code point (but a number of leading bits must be zero as there are far fewer than 232 Unicode code points, needing actually only 21 bits). In contrast, all other Unicode transformation formats are variable-length encodings. Each 32-bit value in UTF-32 represents one Unicode code point and is exactly equal to that code point's numerical value. The main advantage of UTF-32 is that the Unicode code points are directly indexed. Finding the ''Nth'' code point in a sequence of code points is a constant-time operation. In contrast, a variable-length code requires linear-time to count ''N'' code points from the start of the string. This makes UTF-32 a simple replacement in code that uses integers that are incremented by one to examine each location in a string, as was commonly done for ASCII. However, Unicode code ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unicode
Unicode or ''The Unicode Standard'' or TUS is a character encoding standard maintained by the Unicode Consortium designed to support the use of text in all of the world's writing systems that can be digitized. Version 16.0 defines 154,998 Character (computing), characters and 168 script (Unicode), scripts used in various ordinary, literary, academic, and technical contexts. Unicode has largely supplanted the previous environment of a myriad of incompatible character sets used within different locales and on different computer architectures. The entire repertoire of these sets, plus many additional characters, were merged into the single Unicode set. Unicode is used to encode the vast majority of text on the Internet, including most web pages, and relevant Unicode support has become a common consideration in contemporary software development. Unicode is ultimately capable of encoding more than 1.1 million characters. The Unicode character repertoire is synchronized with Univers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big5
Big-5 or Big5 ( zh, t=大五碼) is a Chinese character encoding method used in Taiwan, Hong Kong, and Macau for traditional Chinese characters. The People's Republic of China (PRC), which uses simplified Chinese characters, uses the GB 18030 character set instead (though it can also substitute Big-5 or UTF-8). Big5 gets its name from the consortium of five companies in Taiwan that developed it. Encoding The original Big5 character set is sorted first by usage frequency, second by stroke count, lastly by Kangxi radical. The original Big5 character set lacked many commonly used characters. To solve this problem, each vendor developed its own extension. The ETen extension became part of the current Big5 standard through popularity. The structure of Big5 does not conform to the ISO 2022 standard, but rather bears a certain similarity to the encoding. It is a double-byte character set (DBCS) with the following structure: (the prefix 0x signifying hexadecimal numbers). Sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shift-JIS
Shift JIS (also SJIS, MIME name Shift_JIS, known as PCK in Solaris contexts) is a character encoding for the Japanese language, originally developed by the Japanese company ASCII Corporation in conjunction with Microsoft and standardized as JIS X 0208 Appendix 1. Shift JIS is based on character sets defined within JIS standards (for the single-byte characters) and (for the double-byte characters). , less than 0.05% of surveyed web pages used Shift JIS (actually decoded as its superset Windows-31J encoding), a decline from 1.3% in July 2014. Shift JIS is the third-most declared character encoding for Japanese websites (though in effect it means its superset Windows-31J is used, so it is third-most popular), declared by 1.0% of sites in the .jp domain, while UTF-8 is used by 99% of Japanese websites. Shift JIS is also sometimes used in QR codes (they are a Japanese invention also allowing UTF-8, which may though be preferred use). Structure Shift JIS is an extension ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
