Information: - An operating system (OS) is system software that manages computer hardware and software resources and provides common services for computer programs. All computer programs, excluding firmware, require an operating system to function. - Portable Character Set is a set of 103 characters which , according to the POSIX standard , must be present in any character set . It is a subset of ASCII , lacking some control characters . - IEEE Computer Society (sometimes abbreviated Computer Society or CS) is a professional society of IEEE. Its purpose and scope is "to advance the theory, practice, and application of computer and information processing science and technology" and the "professional standing of its members." The CS is the largest of 39 technical societies organized under the IEEE Technical Activities Board. - The Portable Operating System Interface (POSIX) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines the application programming interface (API), along with command line shells and utility interfaces, for software compatibility with variants of Unix and other operating systems. - In computing, a character encoding is used to represent a repertoire of characters by some kind of an encoding system. Depending on the abstraction level and context, corresponding code points and the resulting code space may be regarded as bit patterns, octets, natural numbers, electrical pulses, etc. A character encoding is used in computation, data storage, and transmission of textual data. Character set, character map, codeset and code page are related, but not identical, terms. - ASCII, abbreviated from American Standard Code for Information Interchange, is a character encoding standard (the Internet Assigned Numbers Authority (IANA) prefers the name US-ASCII). ASCII codes represent text in computers, telecommunications equipment, and other devices. Most modern character-encoding schemes are based on ASCII, although they support many additional characters. - vi is a screen-oriented text editor originally created for the Unix operating system. The portable subset of the behavior of vi and programs based on it, and the ex editor language supported within these programs, is described by (and thus standardized by) the Single Unix Specification and POSIX. - In computing and telecommunication, a control character or non-printing character is a code point (a number) in a character set, that does not represent a written symbol. They are used as in-band signaling to cause effects other than the addition of a symbol to the text. All other characters are mainly printing, printable, or graphic characters, except perhaps for the "space" character (see ASCII printable characters). - The Internet Assigned Numbers Authority (IANA) is a department of ICANN, a nonprofit private American corporation that oversees global IP address allocation, autonomous system number allocation, root zone management in the Domain Name System (DNS), media types, and other Internet Protocol-related symbols and Internet numbers. - Unix (trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, developed starting in the 1970s at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. What is the relationship between 'portable character set' and 'character encoding'?
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