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BinHex
BinHex, originally short for "binary-to-hexadecimal", is a binary-to-text encoding system that was used on the classic Mac OS for sending binary files through e-mail. Originally a hexadecimal encoding, subsequent versions of BinHex are more similar to uuencode, but combined both "forks" of the Mac file system together along with extended file information. BinHexed files take up more space than the original files, but will not be corrupted by non-"8-bit clean" software. History TRS-80 BinHex (.hex) BinHex was originally written in 1981 by Tim Mann for the TRS-80, as a stand-alone version of an encoding scheme originally built into a popular terminal emulator, ST80-III by Lance Micklus. BinHex was used for sending files via major online services such as CompuServe, which were not "8-bit clean" and required ASCII armoring to survive. Not everyone used ST-80, however, so Mann wrote BinHex to allow users of other emulators to use the format. The original ST-80 system worked by con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MacBinary
MacBinary is a file format that combines the two ''forks'' of a classic Mac OS file into a single file, along with Hierarchical File System, HFS's extended metadata. The resulting file is suitable for transmission over File Transfer Protocol, FTP, the World Wide Web, and electronic mail. The documents can also be stored on computers that run operating systems with no HFS support, such as Unix or Microsoft Windows, Windows. MacBinary was widely supported on the Macintosh and was built into most communications programs on that platform. Similar solutions were built into most data compression applications on the Mac, and although these did not require MacBinary to survive transmission across non-Mac systems, MacBinary was often added in these cases to preserve longer filenames and other features. The dual-fork nature of the HFS system was not used on Mac OS X, and MacBinary has largely disappeared. Description In contrast to other computers of the era, Macintosh applications include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASCII Armoring
A binary-to-text encoding is encoding of data in plain text. More precisely, it is an encoding of binary data in a sequence of printable characters. These encodings are necessary for transmission of data when the channel does not allow binary data (such as email or NNTP) or is not 8-bit clean. PGP documentation () uses the term "ASCII armor" for binary-to-text encoding when referring to Base64. Overview The basic need for a binary-to-text encoding comes from a need to communicate arbitrary binary data over preexisting communications protocols that were designed to carry only English language human-readable text. Those communication protocols may only be 7-bit safe (and within that avoid certain ASCII control codes), and may require line breaks at certain maximum intervals, and may not maintain whitespace. Thus, only the 94 printable ASCII characters are "safe" to use to convey data. Description The ASCII text-encoding standard uses 7 bits to encode characters. With this it is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary-to-text Encoding
A binary-to-text encoding is encoding of data in plain text. More precisely, it is an encoding of binary data in a sequence of printable characters. These encodings are necessary for transmission of data when the channel does not allow binary data (such as email or NNTP) or is not 8-bit clean. PGP documentation () uses the term "ASCII armor" for binary-to-text encoding when referring to Base64. Overview The basic need for a binary-to-text encoding comes from a need to communicate arbitrary binary data over preexisting communications protocols that were designed to carry only English language human-readable text. Those communication protocols may only be 7-bit safe (and within that avoid certain ASCII control codes), and may require line breaks at certain maximum intervals, and may not maintain whitespace. Thus, only the 94 printable ASCII characters are "safe" to use to convey data. Description The ASCII text-encoding standard uses 7 bits to encode characters. With this it is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resource Fork
The resource fork is a fork (file system), fork or section of a computer file, file on Apple Inc., Apple's classic Mac OS operating system, which was also carried over to the modern macOS for compatibility, used to store structured data along with the unstructured data stored within the data fork. A resource fork stores information in a specific form, containing details such as icon bitmaps, the shapes of windows, definitions of menus and their contents, and application code (machine code). For example, a word processing file might store its text in the data fork, while storing any embedded images in the same file's resource fork. The resource fork is used mostly by executables, but every file is able to have a resource fork. The Macintosh file system Originally conceived and implemented by programmer Bruce Horn, the resource fork was used for three purposes with Hierarchical File System, Macintosh file system: * It was used to store all graphical data on disk until it was neede ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
8-bit Clean
''8-bit clean'' is an attribute of computer systems, communication channels, and other devices and software, that handle 8-bit character encodings correctly. Such encoding include the ISO 8859 series and the UTF-8 encoding of Unicode. History Until the early 1990s, many programs and data transmission channels were character-oriented and treated some characters, e.g., ETX, as control characters. Other assumed a stream of seven-bit characters, with values between 0 and 127; for example, the ASCII standard used only seven bits per character, avoiding an 8-bit representation in order to save on data transmission costs. On computers and data links using 8-bit bytes this left the top bit of each byte free for use as a parity, flag bit, or meta data control bit. 7-bit systems and data links are unable to directly handle more complex character codes which are commonplace in non-English-speaking countries with larger alphabets. Binary files of octets cannot be transmitted through 7 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Info-Mac
Info-Mac is an online community, news aggregator and shareware file hosting service covering Apple Inc. products, including the iPhone, iPod and especially the Macintosh. Established in 1984 as an electronic mailing list, Info-Mac is notable as being the first online community for Apple's then-new Macintosh computer. Info-Mac was the dominant Internet resource for Mac OS software and community-based support throughout the 1980s and early 1990s. Original format Info-Mac consisted of two distinct services: the ''Info-Mac Archive'', a user-submitted collection of nearly all contemporary freeware and shareware available for the Macintosh, and the ''Info-Mac Digest'', an electronic mailing list open to public participation. Both the Info-Mac Archive and Info-Mac Digest were operated by volunteers. Info-Mac Digest The Info-Mac Digest was published daily via Stanford University servers, and was itself archived on the Info-Mac Archive. At its height, the Info-Mac Digest was read da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classic Mac OS
Mac OS (originally System Software; retronym: Classic Mac OS) is the series of operating systems developed for the Macintosh family of personal computers by Apple Computer from 1984 to 2001, starting with System 1 and ending with Mac OS 9. The Macintosh operating system is credited with having popularized the graphical user interface concept. It was included with every Macintosh that was sold during the era in which it was developed, and many updates to the system software were done in conjunction with the introduction of new Macintosh systems. Apple released the Macintosh 128K, original Macintosh on January 24, 1984. The System 1, first version of the system software, which had no official name, was partially based on the Lisa OS, which Apple previously released for the Apple Lisa, Lisa computer in 1983. As part of an agreement allowing Xerox to buy Share (finance), shares in Apple at a favorable price, it also used concepts from the Xerox PARC Xerox Alto, Alto computer, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resource Fork
The resource fork is a fork (file system), fork or section of a computer file, file on Apple Inc., Apple's classic Mac OS operating system, which was also carried over to the modern macOS for compatibility, used to store structured data along with the unstructured data stored within the data fork. A resource fork stores information in a specific form, containing details such as icon bitmaps, the shapes of windows, definitions of menus and their contents, and application code (machine code). For example, a word processing file might store its text in the data fork, while storing any embedded images in the same file's resource fork. The resource fork is used mostly by executables, but every file is able to have a resource fork. The Macintosh file system Originally conceived and implemented by programmer Bruce Horn, the resource fork was used for three purposes with Hierarchical File System, Macintosh file system: * It was used to store all graphical data on disk until it was neede ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexadecimal
In mathematics and computing, the hexadecimal (also base-16 or simply hex) numeral system is a positional numeral system that represents numbers using a radix (base) of 16. Unlike the decimal system representing numbers using 10 symbols, hexadecimal uses 16 distinct symbols, most often the symbols "0"–"9" to represent values 0 to 9, and "A"–"F" (or alternatively "a"–"f") to represent values from 10 to 15. Software developers and system designers widely use hexadecimal numbers because they provide a human-friendly representation of binary-coded values. Each hexadecimal digit represents four bits (binary digits), also known as a nibble (or nybble). For example, an 8-bit byte can have values ranging from 00000000 to 11111111 in binary form, which can be conveniently represented as 00 to FF 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, a number of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MS BASIC For Macintosh
MS BASIC for Macintosh was a dialect of Microsoft BASIC for Macintosh. It was one of the first Microsoft BASIC variants to have optional line numbering, predating QuickBASIC. It was provided in two versions, one with standard Floating point, binary floating point and another with Decimal floating point, decimal arithmetic. References BASIC programming language Discontinued BASICs Classic Mac OS programming tools Microsoft programming languages 1983 software {{computer-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ZMODEM
ZMODEM is an inline file transfer protocol developed by Chuck Forsberg in 1986, in a project funded by Telenet in order to improve file transfers on their X.25 network. In addition to dramatically improved performance compared to older protocols, ZMODEM offered restartable transfers, auto-start by the sender, an expanded 32-bit CRC, and control character quoting supporting 8-bit clean transfers, allowing it to be used on networks that would not pass control characters. In contrast to most transfer protocols developed for bulletin board systems (BBSs), ZMODEM was not directly based on, nor compatible with, the seminal XMODEM. Many variants of XMODEM had been developed in order to address one or more of its shortcomings, and most remained backward compatible and would successfully complete transfers with "classic" XMODEM implementations. This list includes Forsberg's own YMODEM. ZMODEM eschewed backward compatibility in favor of producing a radically improved protocol. It perfor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Run Length Encoding
Run-length encoding (RLE) is a form of lossless data compression in which ''runs'' of data (sequences in which the same data value occurs in many consecutive data elements) are stored as a single data value and count, rather than as the original run. This is most efficient on data that contains many such runs, for example, simple graphic images such as icons, line drawings, Conway's Game of Life, and animations. For files that do not have many runs, RLE could increase the file size. RLE may also be used to refer to an early graphics file format supported by CompuServe for compressing black and white images, but was widely supplanted by their later Graphics Interchange Format (GIF). RLE also refers to a little-used image format in Windows 3.x, with the extension rle, which is a run-length encoded bitmap, used to compress the Windows 3.x startup screen. Example Consider a screen containing plain black text on a solid white background. There will be many long runs of white pixel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
