ASCII

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Not to be confused with MS Windows-1252 or other types of extended ASCII. ASCII_sentence_0

This article is about the character encoding. ASCII_sentence_1

For other uses, see ASCII (disambiguation). ASCII_sentence_2

ASCII_table_infobox_0

ASCIIASCII_table_caption_0
MIME / IANAASCII_header_cell_0_0_0 us-asciiASCII_cell_0_0_1
Alias(es)ASCII_header_cell_0_1_0 ISO-IR-006, ANSI_X3.4-1968, ANSI_X3.4-1986, ISO_646.irv:1991, ISO646-US, us, IBM367, cp367ASCII_cell_0_1_1
Language(s)ASCII_header_cell_0_2_0 EnglishASCII_cell_0_2_1
ClassificationASCII_header_cell_0_3_0 ISO 646 seriesASCII_cell_0_3_1
ExtensionsASCII_header_cell_0_4_0 ASCII_cell_0_4_1
Preceded byASCII_header_cell_0_5_0 ITA 2, FIELDATAASCII_cell_0_5_1
Succeeded byASCII_header_cell_0_6_0 ISO 8859, UnicodeASCII_cell_0_6_1

ASCII (/ˈæskiː/ (listen) ASS-kee), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII_sentence_3

ASCII codes represent text in computers, telecommunications equipment, and other devices. ASCII_sentence_4

Most modern character-encoding schemes are based on ASCII, although they support many additional characters. ASCII_sentence_5

The Internet Assigned Numbers Authority (IANA) prefers the name US-ASCII for this character encoding. ASCII_sentence_6

ASCII is one of the IEEE milestones. ASCII_sentence_7

Overview ASCII_section_0

ASCII was developed from telegraph code. ASCII_sentence_8

Its first commercial use was as a seven-bit teleprinter code promoted by Bell data services. ASCII_sentence_9

Work on the ASCII standard began on October 6, 1960, with the first meeting of the American Standards Association's (ASA) (now the American National Standards Institute or ANSI) X3.2 subcommittee. ASCII_sentence_10

The first edition of the standard was published in 1963, underwent a major revision during 1967, and experienced its most recent update during 1986. ASCII_sentence_11

Compared to earlier telegraph codes, the proposed Bell code and ASCII were both ordered for more convenient sorting (i.e., alphabetization) of lists, and added features for devices other than teleprinters. ASCII_sentence_12

The use of ASCII format for Network Interchange was described in 1969. ASCII_sentence_13

That document was formally elevated to an Internet Standard in 2015. ASCII_sentence_14

Originally based on the English alphabet, ASCII encodes 128 specified characters into seven-bit integers as shown by the ASCII chart above. ASCII_sentence_15

Ninety-five of the encoded characters are printable: these include the digits 0 to 9, lowercase letters a to z, uppercase letters A to Z, and punctuation symbols. ASCII_sentence_16

In addition, the original ASCII specification included 33 non-printing control codes which originated with Teletype machines; most of these are now obsolete, although a few are still commonly used, such as the carriage return, line feed and tab codes. ASCII_sentence_17

For example, lowercase i would be represented in the ASCII encoding by binary 1101001 = hexadecimal 69 (i is the ninth letter) = decimal 105. ASCII_sentence_18

History ASCII_section_1

The American Standard Code for Information Interchange (ASCII) was developed under the auspices of a committee of the American Standards Association (ASA), called the X3 committee, by its X3.2 (later X3L2) subcommittee, and later by that subcommittee's X3.2.4 working group (now INCITS). ASCII_sentence_19

The ASA became the United States of America Standards Institute (USASI) and ultimately the American National Standards Institute (ANSI). ASCII_sentence_20

With the other special characters and control codes filled in, ASCII was published as ASA X3.4-1963, leaving 28 code positions without any assigned meaning, reserved for future standardization, and one unassigned control code. ASCII_sentence_21

There was some debate at the time whether there should be more control characters rather than the lowercase alphabet. ASCII_sentence_22

The indecision did not last long: during May 1963 the CCITT Working Party on the New Telegraph Alphabet proposed to assign lowercase characters to sticks 6 and 7, and International Organization for Standardization TC 97 SC 2 voted during October to incorporate the change into its draft standard. ASCII_sentence_23

The X3.2.4 task group voted its approval for the change to ASCII at its May 1963 meeting. ASCII_sentence_24

Locating the lowercase letters in sticks 6 and 7 caused the characters to differ in bit pattern from the upper case by a single bit, which simplified case-insensitive character matching and the construction of keyboards and printers. ASCII_sentence_25

The X3 committee made other changes, including other new characters (the brace and vertical bar characters), renaming some control characters (SOM became start of header (SOH)) and moving or removing others (RU was removed). ASCII_sentence_26

ASCII was subsequently updated as USAS X3.4-1967, then USAS X3.4-1968, ANSI X3.4-1977, and finally, ANSI X3.4-1986. ASCII_sentence_27

Revisions of the ASCII standard: ASCII_sentence_28

ASCII_unordered_list_0

  • ASA X3.4-1963ASCII_item_0_0
  • ASA X3.4-1965 (approved, but not published, nevertheless used by IBM 2260 & 2265 Display Stations and IBM 2848 Display Control)ASCII_item_0_1
  • USAS X3.4-1967ASCII_item_0_2
  • USAS X3.4-1968ASCII_item_0_3
  • ANSI X3.4-1977ASCII_item_0_4
  • ANSI X3.4-1986ASCII_item_0_5
  • ANSI X3.4-1986 (R1992)ASCII_item_0_6
  • ANSI X3.4-1986 (R1997)ASCII_item_0_7
  • ANSI INCITS 4-1986 (R2002)ASCII_item_0_8
  • ANSI INCITS 4-1986 (R2007)ASCII_item_0_9
  • (ANSI) INCITS 4-1986[R2012]ASCII_item_0_10
  • (ANSI) INCITS 4-1986[R2017]ASCII_item_0_11

In the X3.15 standard, the X3 committee also addressed how ASCII should be transmitted (least significant bit first), and how it should be recorded on perforated tape. ASCII_sentence_29

They proposed a 9-track standard for magnetic tape, and attempted to deal with some punched card formats. ASCII_sentence_30

Design considerations ASCII_section_2

Bit width ASCII_section_3

The X3.2 subcommittee designed ASCII based on the earlier teleprinter encoding systems. ASCII_sentence_31

Like other character encodings, ASCII specifies a correspondence between digital bit patterns and character symbols (i.e. graphemes and control characters). ASCII_sentence_32

This allows digital devices to communicate with each other and to process, store, and communicate character-oriented information such as written language. ASCII_sentence_33

Before ASCII was developed, the encodings in use included 26 alphabetic characters, 10 numerical digits, and from 11 to 25 special graphic symbols. ASCII_sentence_34

To include all these, and control characters compatible with the Comité Consultatif International Téléphonique et Télégraphique (CCITT) International Telegraph Alphabet No. ASCII_sentence_35 2 (ITA2) standard of 1924, FIELDATA (1956), and early EBCDIC (1963), more than 64 codes were required for ASCII. ASCII_sentence_36

ITA2 were in turn based on the 5-bit telegraph code Émile Baudot invented in 1870 and patented in 1874. ASCII_sentence_37

The committee debated the possibility of a shift function (like in ITA2), which would allow more than 64 codes to be represented by a six-bit code. ASCII_sentence_38

In a shifted code, some character codes determine choices between options for the following character codes. ASCII_sentence_39

It allows compact encoding, but is less reliable for data transmission, as an error in transmitting the shift code typically makes a long part of the transmission unreadable. ASCII_sentence_40

The standards committee decided against shifting, and so ASCII required at least a seven-bit code. ASCII_sentence_41

The committee considered an eight-bit code, since eight bits (octets) would allow two four-bit patterns to efficiently encode two digits with binary-coded decimal. ASCII_sentence_42

However, it would require all data transmission to send eight bits when seven could suffice. ASCII_sentence_43

The committee voted to use a seven-bit code to minimize costs associated with data transmission. ASCII_sentence_44

Since perforated tape at the time could record eight bits in one position, it also allowed for a parity bit for error checking if desired. ASCII_sentence_45

Eight-bit machines (with octets as the native data type) that did not use parity checking typically set the eighth bit to 0. ASCII_sentence_46

In some printers, the high bit was used to enable Italics printing. ASCII_sentence_47

Internal organization ASCII_section_4

The code itself was patterned so that most control codes were together and all graphic codes were together, for ease of identification. ASCII_sentence_48

The first two so-called ASCII sticks (32 positions) were reserved for control characters. ASCII_sentence_49

The "space" character had to come before graphics to make sorting easier, so it became position 20hex; for the same reason, many special signs commonly used as separators were placed before digits. ASCII_sentence_50

The committee decided it was important to support uppercase 64-character alphabets, and chose to pattern ASCII so it could be reduced easily to a usable 64-character set of graphic codes, as was done in the DEC SIXBIT code (1963). ASCII_sentence_51

Lowercase letters were therefore not interleaved with uppercase. ASCII_sentence_52

To keep options available for lowercase letters and other graphics, the special and numeric codes were arranged before the letters, and the letter A was placed in position 41hex to match the draft of the corresponding British standard. ASCII_sentence_53

The digits 0–9 are prefixed with 011, but the remaining 4 bits correspond to their respective values in binary, making conversion with binary-coded decimal straightforward. ASCII_sentence_54

Many of the non-alphanumeric characters were positioned to correspond to their shifted position on typewriters; an important subtlety is that these were based on mechanical typewriters, not electric typewriters. ASCII_sentence_55

Mechanical typewriters followed the standard set by the Remington No. ASCII_sentence_56

2 (1878), the first typewriter with a shift key, and the shifted values of 23456789- were "#$%_&'() – early typewriters omitted 0 and 1, using O (capital letter o) and l (lowercase letter L) instead, but 1! ASCII_sentence_57

and 0) pairs became standard once 0 and 1 became common. ASCII_sentence_58

Thus, in ASCII ! ASCII_sentence_59

"#$% were placed in the second stick, positions 1–5, corresponding to the digits 1–5 in the adjacent stick. ASCII_sentence_60

The parentheses could not correspond to 9 and 0, however, because the place corresponding to 0 was taken by the space character. ASCII_sentence_61

This was accommodated by removing _ (underscore) from 6 and shifting the remaining characters, which corresponded to many European typewriters that placed the parentheses with 8 and 9. ASCII_sentence_62

This discrepancy from typewriters led to bit-paired keyboards, notably the Teletype Model 33, which used the left-shifted layout corresponding to ASCII, not to traditional mechanical typewriters. ASCII_sentence_63

Electric typewriters, notably the IBM Selectric (1961), used a somewhat different layout that has become standard on computers – following the IBM PC (1981), especially Model M (1984) – and thus shift values for symbols on modern keyboards do not correspond as closely to the ASCII table as earlier keyboards did. ASCII_sentence_64

The /? ASCII_sentence_65

pair also dates to the No. ASCII_sentence_66

2, and the ,< .> pairs were used on some keyboards (others, including the No. ASCII_sentence_67

2, did not shift , (comma) or . ASCII_sentence_68

(full stop) so they could be used in uppercase without unshifting). ASCII_sentence_69

However, ASCII split the ;: pair (dating to No. ASCII_sentence_70

2), and rearranged mathematical symbols (varied conventions, commonly -* =+) to :* ;+ -=. ASCII_sentence_71

Some common characters were not included, notably ½¼¢, while ^`~ were included as diacritics for international use, and <> for mathematical use, together with the simple line characters \| (in addition to common /). ASCII_sentence_72

The @ symbol was not used in continental Europe and the committee expected it would be replaced by an accented À in the French variation, so the @ was placed in position 40hex, right before the letter A. ASCII_sentence_73

The control codes felt essential for data transmission were the start of message (SOM), end of address (EOA), end of message (EOM), end of transmission (EOT), "who are you?" ASCII_sentence_74

(WRU), "are you?" ASCII_sentence_75

(RU), a reserved device control (DC0), synchronous idle (SYNC), and acknowledge (ACK). ASCII_sentence_76

These were positioned to maximize the Hamming distance between their bit patterns. ASCII_sentence_77

Character order ASCII_section_5

ASCII-code order is also called ASCIIbetical order. ASCII_sentence_78

Collation of data is sometimes done in this order rather than "standard" alphabetical order (collating sequence). ASCII_sentence_79

The main deviations in ASCII order are: ASCII_sentence_80

ASCII_unordered_list_1

  • All uppercase come before lowercase letters; for example, "Z" precedes "a"ASCII_item_1_12
  • Digits and many punctuation marks come before lettersASCII_item_1_13

An intermediate order converts uppercase letters to lowercase before comparing ASCII values. ASCII_sentence_81

Character groups ASCII_section_6

Control characters ASCII_section_7

Main article: Control character ASCII_sentence_82

ASCII reserves the first 32 codes (numbers 0–31 decimal) for control characters: codes originally intended not to represent printable information, but rather to control devices (such as printers) that make use of ASCII, or to provide meta-information about data streams such as those stored on magnetic tape. ASCII_sentence_83

For example, character 10 represents the "line feed" function (which causes a printer to advance its paper), and character 8 represents "backspace". ASCII_sentence_84

RFC  refers to control characters that do not include carriage return, line feed or white space as non-whitespace control characters. ASCII_sentence_85

Except for the control characters that prescribe elementary line-oriented formatting, ASCII does not define any mechanism for describing the structure or appearance of text within a document. ASCII_sentence_86

Other schemes, such as markup languages, address page and document layout and formatting. ASCII_sentence_87

The original ASCII standard used only short descriptive phrases for each control character. ASCII_sentence_88

The ambiguity this caused was sometimes intentional, for example where a character would be used slightly differently on a terminal link than on a data stream, and sometimes accidental, for example with the meaning of "delete". ASCII_sentence_89

Probably the most influential single device on the interpretation of these characters was the Teletype Model 33 ASR, which was a printing terminal with an available paper tape reader/punch option. ASCII_sentence_90

Paper tape was a very popular medium for long-term program storage until the 1980s, less costly and in some ways less fragile than magnetic tape. ASCII_sentence_91

In particular, the Teletype Model 33 machine assignments for codes 17 (Control-Q, DC1, also known as XON), 19 (Control-S, DC3, also known as XOFF), and 127 (Delete) became de facto standards. ASCII_sentence_92

The Model 33 was also notable for taking the description of Control-G (code 7, BEL, meaning audibly alert the operator) literally, as the unit contained an actual bell which it rang when it received a BEL character. ASCII_sentence_93

Because the keytop for the O key also showed a left-arrow symbol (from ASCII-1963, which had this character instead of underscore), a noncompliant use of code 15 (Control-O, Shift In) interpreted as "delete previous character" was also adopted by many early timesharing systems but eventually became neglected. ASCII_sentence_94

When a Teletype 33 ASR equipped with the automatic paper tape reader received a Control-S (XOFF, an abbreviation for transmit off), it caused the tape reader to stop; receiving Control-Q (XON, "transmit on") caused the tape reader to resume. ASCII_sentence_95

This technique became adopted by several early computer operating systems as a "handshaking" signal warning a sender to stop transmission because of impending overflow; it persists to this day in many systems as a manual output control technique. ASCII_sentence_96

On some systems Control-S retains its meaning but Control-Q is replaced by a second Control-S to resume output. ASCII_sentence_97

The 33 ASR also could be configured to employ Control-R (DC2) and Control-T (DC4) to start and stop the tape punch; on some units equipped with this function, the corresponding control character lettering on the keycap above the letter was TAPE and TAPE respectively. ASCII_sentence_98

Delete & Backspace ASCII_section_8

The Teletype could not move the head backwards, so it did not put a key on the keyboard to send a BS (backspace). ASCII_sentence_99

Instead there was a key marked RUB OUT that sent code 127 (DEL). ASCII_sentence_100

The purpose of this key was to erase mistakes in a hand-typed paper tape: the operator had to push a button on the tape punch to back it up, then type the rubout, which punched all holes and replaced the mistake with a character that was intended to be ignored. ASCII_sentence_101

Teletypes were commonly used for the less-expensive computers from Digital Equipment Corporation, so these systems had to use the available key and thus the DEL code to erase the previous character. ASCII_sentence_102

Because of this, DEC video terminals (by default) sent the DEL code for the key marked "Backspace" while the key marked "Delete" sent an escape sequence, while many other terminals sent BS for the Backspace key. ASCII_sentence_103

The Unix terminal driver could only use one code to erase the previous character, this could be set to BS or DEL, but not both, resulting in a long period of annoyance where users had to correct it depending on what terminal they were using (shells that allow line editing, such as ksh, bash, and zsh, understand both). ASCII_sentence_104

The assumption that no key sent a BS caused Control+H to be used for other purposes, such as the "help" prefix command in GNU Emacs. ASCII_sentence_105

Escape ASCII_section_9

Many more of the control codes have been given meanings quite different from their original ones. ASCII_sentence_106

The "escape" character (ESC, code 27), for example, was intended originally to allow sending other control characters as literals instead of invoking their meaning. ASCII_sentence_107

This is the same meaning of "escape" encountered in URL encodings, C language strings, and other systems where certain characters have a reserved meaning. ASCII_sentence_108

Over time this meaning has been co-opted and has eventually been changed. ASCII_sentence_109

In modern use, an ESC sent to the terminal usually indicates the start of a command sequence usually in the form of a so-called "ANSI escape code" (or, more properly, a "Control Sequence Introducer") from ECMA-48 (1972) and its successors, beginning with ESC followed by a "[" (left-bracket) character. ASCII_sentence_110

An ESC sent from the terminal is most often used as an out-of-band character used to terminate an operation, as in the TECO and vi text editors. ASCII_sentence_111

In graphical user interface (GUI) and windowing systems, ESC generally causes an application to abort its current operation or to exit (terminate) altogether. ASCII_sentence_112

End of Line ASCII_section_10

The inherent ambiguity of many control characters, combined with their historical usage, created problems when transferring "plain text" files between systems. ASCII_sentence_113

The best example of this is the newline problem on various operating systems. ASCII_sentence_114

Teletype machines required that a line of text be terminated with both "Carriage Return" (which moves the printhead to the beginning of the line) and "Line Feed" (which advances the paper one line without moving the printhead). ASCII_sentence_115

The name "Carriage Return" comes from the fact that on a manual typewriter the carriage holding the paper moved while the position where the typebars struck the ribbon remained stationary. ASCII_sentence_116

The entire carriage had to be pushed (returned) to the right in order to position the left margin of the paper for the next line. ASCII_sentence_117

DEC operating systems (OS/8, RT-11, RSX-11, RSTS, TOPS-10, etc.) used both characters to mark the end of a line so that the console device (originally Teletype machines) would work. ASCII_sentence_118

By the time so-called "glass TTYs" (later called CRTs or terminals) came along, the convention was so well established that backward compatibility necessitated continuing the convention. ASCII_sentence_119

When Gary Kildall created CP/M he was inspired by some command line interface conventions used in DEC's RT-11. ASCII_sentence_120

Until the introduction of PC DOS in 1981, IBM had no hand in this because their 1970s operating systems used EBCDIC instead of ASCII and they were oriented toward punch-card input and line printer output on which the concept of carriage return was meaningless. ASCII_sentence_121

IBM's PC DOS (also marketed as MS-DOS by Microsoft) inherited the convention by virtue of being loosely based on CP/M, and Windows inherited it from MS-DOS. ASCII_sentence_122

Unfortunately, requiring two characters to mark the end of a line introduces unnecessary complexity and questions as to how to interpret each character when encountered alone. ASCII_sentence_123

To simplify matters plain text data streams, including files, on Multics used line feed (LF) alone as a line terminator. ASCII_sentence_124

Unix and Unix-like systems, and Amiga systems, adopted this convention from Multics. ASCII_sentence_125

The original Macintosh OS, Apple DOS, and ProDOS, on the other hand, used carriage return (CR) alone as a line terminator; however, since Apple replaced these operating systems with the Unix-based macOS operating system, they now use line feed (LF) as well. ASCII_sentence_126

The Radio Shack TRS-80 also used a lone CR to terminate lines. ASCII_sentence_127

Computers attached to the ARPANET included machines running operating systems such as TOPS-10 and TENEX using CR-LF line endings, machines running operating systems such as Multics using LF line endings, and machines running operating systems such as OS/360 that represented lines as a character count followed by the characters of the line and that used EBCDIC rather than ASCII. ASCII_sentence_128

The Telnet protocol defined an ASCII "Network Virtual Terminal" (NVT), so that connections between hosts with different line-ending conventions and character sets could be supported by transmitting a standard text format over the network. ASCII_sentence_129

Telnet used ASCII along with CR-LF line endings, and software using other conventions would translate between the local conventions and the NVT. ASCII_sentence_130

The adopted the Telnet protocol, including use of the Network Virtual Terminal, for use when transmitting commands and transferring data in the default ASCII mode. ASCII_sentence_131

This adds complexity to implementations of those protocols, and to other network protocols, such as those used for E-mail and the World Wide Web, on systems not using the NVT's CR-LF line-ending convention. ASCII_sentence_132

End of File/Stream ASCII_section_11

The PDP-6 monitor, and its PDP-10 successor TOPS-10, used Control-Z (SUB) as an end-of-file indication for input from a terminal. ASCII_sentence_133

Some operating systems such as CP/M tracked file length only in units of disk blocks and used Control-Z to mark the end of the actual text in the file. ASCII_sentence_134

For these reasons, EOF, or , was used colloquially and conventionally as a three-letter acronym for Control-Z instead of SUBstitute. ASCII_sentence_135

The end-of-text code (ETX), also known as Control-C, was inappropriate for a variety of reasons, while using Z as the control code to end a file is analogous to it ending the alphabet and serves as a very convenient mnemonic aid. ASCII_sentence_136

A historically common and still prevalent convention uses the ETX code convention to interrupt and halt a program via an input data stream, usually from a keyboard. ASCII_sentence_137

In C library and Unix conventions, the null character is used to terminate text strings; such null-terminated strings can be known in abbreviation as ASCIZ or ASCIIZ, where here Z stands for "zero". ASCII_sentence_138

Control code chart ASCII_section_12

ASCII_table_general_1

BinaryASCII_header_cell_1_0_0 OctASCII_header_cell_1_0_1 DecASCII_header_cell_1_0_2 HexASCII_header_cell_1_0_3 AbbreviationASCII_header_cell_1_0_4 ASCII_header_cell_1_0_7 ASCII_header_cell_1_0_8 ASCII_header_cell_1_0_9 Name (1967)ASCII_header_cell_1_0_10
1963ASCII_header_cell_1_1_0 1965ASCII_header_cell_1_1_1 1967ASCII_header_cell_1_1_2
000 0000ASCII_cell_1_2_0 000ASCII_cell_1_2_1 0ASCII_cell_1_2_2 00ASCII_cell_1_2_3 NULLASCII_cell_1_2_4 NULASCII_cell_1_2_5 ASCII_cell_1_2_7 ^@ASCII_cell_1_2_8 \0ASCII_cell_1_2_9 NullASCII_cell_1_2_10
000 0001ASCII_cell_1_3_0 001ASCII_cell_1_3_1 1ASCII_cell_1_3_2 01ASCII_cell_1_3_3 SOMASCII_cell_1_3_4 SOHASCII_cell_1_3_5 ASCII_cell_1_3_7 ^AASCII_cell_1_3_8 ASCII_cell_1_3_9 Start of HeadingASCII_cell_1_3_10
000 0010ASCII_cell_1_4_0 002ASCII_cell_1_4_1 2ASCII_cell_1_4_2 02ASCII_cell_1_4_3 EOAASCII_cell_1_4_4 STXASCII_cell_1_4_5 ASCII_cell_1_4_7 ^BASCII_cell_1_4_8 ASCII_cell_1_4_9 Start of TextASCII_cell_1_4_10
000 0011ASCII_cell_1_5_0 003ASCII_cell_1_5_1 3ASCII_cell_1_5_2 03ASCII_cell_1_5_3 EOMASCII_cell_1_5_4 ETXASCII_cell_1_5_5 ASCII_cell_1_5_7 ^CASCII_cell_1_5_8 ASCII_cell_1_5_9 End of TextASCII_cell_1_5_10
000 0100ASCII_cell_1_6_0 004ASCII_cell_1_6_1 4ASCII_cell_1_6_2 04ASCII_cell_1_6_3 EOTASCII_cell_1_6_4 ASCII_cell_1_6_7 ^DASCII_cell_1_6_8 ASCII_cell_1_6_9 End of TransmissionASCII_cell_1_6_10
000 0101ASCII_cell_1_7_0 005ASCII_cell_1_7_1 5ASCII_cell_1_7_2 05ASCII_cell_1_7_3 WRUASCII_cell_1_7_4 ENQASCII_cell_1_7_5 ASCII_cell_1_7_7 ^EASCII_cell_1_7_8 ASCII_cell_1_7_9 EnquiryASCII_cell_1_7_10
000 0110ASCII_cell_1_8_0 006ASCII_cell_1_8_1 6ASCII_cell_1_8_2 06ASCII_cell_1_8_3 RUASCII_cell_1_8_4 ACKASCII_cell_1_8_5 ASCII_cell_1_8_7 ^FASCII_cell_1_8_8 ASCII_cell_1_8_9 AcknowledgementASCII_cell_1_8_10
000 0111ASCII_cell_1_9_0 007ASCII_cell_1_9_1 7ASCII_cell_1_9_2 07ASCII_cell_1_9_3 BELLASCII_cell_1_9_4 BELASCII_cell_1_9_5 ASCII_cell_1_9_7 ^GASCII_cell_1_9_8 \aASCII_cell_1_9_9 BellASCII_cell_1_9_10
000 1000ASCII_cell_1_10_0 010ASCII_cell_1_10_1 8ASCII_cell_1_10_2 08ASCII_cell_1_10_3 FE0ASCII_cell_1_10_4 BSASCII_cell_1_10_5 ASCII_cell_1_10_7 ^HASCII_cell_1_10_8 \bASCII_cell_1_10_9 BackspaceASCII_cell_1_10_10
000 1001ASCII_cell_1_11_0 011ASCII_cell_1_11_1 9ASCII_cell_1_11_2 09ASCII_cell_1_11_3 HT/SKASCII_cell_1_11_4 HTASCII_cell_1_11_5 ASCII_cell_1_11_7 ^IASCII_cell_1_11_8 \tASCII_cell_1_11_9 Horizontal TabASCII_cell_1_11_10
000 1010ASCII_cell_1_12_0 012ASCII_cell_1_12_1 10ASCII_cell_1_12_2 0AASCII_cell_1_12_3 LFASCII_cell_1_12_4 ASCII_cell_1_12_7 ^JASCII_cell_1_12_8 \nASCII_cell_1_12_9 Line FeedASCII_cell_1_12_10
000 1011ASCII_cell_1_13_0 013ASCII_cell_1_13_1 11ASCII_cell_1_13_2 0BASCII_cell_1_13_3 VTABASCII_cell_1_13_4 VTASCII_cell_1_13_5 ASCII_cell_1_13_7 ^KASCII_cell_1_13_8 \vASCII_cell_1_13_9 Vertical TabASCII_cell_1_13_10
000 1100ASCII_cell_1_14_0 014ASCII_cell_1_14_1 12ASCII_cell_1_14_2 0CASCII_cell_1_14_3 FFASCII_cell_1_14_4 ASCII_cell_1_14_7 ^LASCII_cell_1_14_8 \fASCII_cell_1_14_9 Form FeedASCII_cell_1_14_10
000 1101ASCII_cell_1_15_0 015ASCII_cell_1_15_1 13ASCII_cell_1_15_2 0DASCII_cell_1_15_3 CRASCII_cell_1_15_4 ASCII_cell_1_15_7 ^MASCII_cell_1_15_8 \rASCII_cell_1_15_9 Carriage ReturnASCII_cell_1_15_10
000 1110ASCII_cell_1_16_0 016ASCII_cell_1_16_1 14ASCII_cell_1_16_2 0EASCII_cell_1_16_3 SOASCII_cell_1_16_4 ASCII_cell_1_16_7 ^NASCII_cell_1_16_8 ASCII_cell_1_16_9 Shift OutASCII_cell_1_16_10
000 1111ASCII_cell_1_17_0 017ASCII_cell_1_17_1 15ASCII_cell_1_17_2 0FASCII_cell_1_17_3 SIASCII_cell_1_17_4 ASCII_cell_1_17_7 ^OASCII_cell_1_17_8 ASCII_cell_1_17_9 Shift InASCII_cell_1_17_10
001 0000ASCII_cell_1_18_0 020ASCII_cell_1_18_1 16ASCII_cell_1_18_2 10ASCII_cell_1_18_3 DC0ASCII_cell_1_18_4 DLEASCII_cell_1_18_5 ASCII_cell_1_18_7 ^PASCII_cell_1_18_8 ASCII_cell_1_18_9 Data Link EscapeASCII_cell_1_18_10
001 0001ASCII_cell_1_19_0 021ASCII_cell_1_19_1 17ASCII_cell_1_19_2 11ASCII_cell_1_19_3 DC1ASCII_cell_1_19_4 ASCII_cell_1_19_7 ^QASCII_cell_1_19_8 ASCII_cell_1_19_9 Device Control 1 (often XON)ASCII_cell_1_19_10
001 0010ASCII_cell_1_20_0 022ASCII_cell_1_20_1 18ASCII_cell_1_20_2 12ASCII_cell_1_20_3 DC2ASCII_cell_1_20_4 ASCII_cell_1_20_7 ^RASCII_cell_1_20_8 ASCII_cell_1_20_9 Device Control 2ASCII_cell_1_20_10
001 0011ASCII_cell_1_21_0 023ASCII_cell_1_21_1 19ASCII_cell_1_21_2 13ASCII_cell_1_21_3 DC3ASCII_cell_1_21_4 ASCII_cell_1_21_7 ^SASCII_cell_1_21_8 ASCII_cell_1_21_9 Device Control 3 (often XOFF)ASCII_cell_1_21_10
001 0100ASCII_cell_1_22_0 024ASCII_cell_1_22_1 20ASCII_cell_1_22_2 14ASCII_cell_1_22_3 DC4ASCII_cell_1_22_4 ASCII_cell_1_22_7 ^TASCII_cell_1_22_8 ASCII_cell_1_22_9 Device Control 4ASCII_cell_1_22_10
001 0101ASCII_cell_1_23_0 025ASCII_cell_1_23_1 21ASCII_cell_1_23_2 15ASCII_cell_1_23_3 ERRASCII_cell_1_23_4 NAKASCII_cell_1_23_5 ASCII_cell_1_23_7 ^UASCII_cell_1_23_8 ASCII_cell_1_23_9 Negative AcknowledgementASCII_cell_1_23_10
001 0110ASCII_cell_1_24_0 026ASCII_cell_1_24_1 22ASCII_cell_1_24_2 16ASCII_cell_1_24_3 SYNCASCII_cell_1_24_4 SYNASCII_cell_1_24_5 ASCII_cell_1_24_7 ^VASCII_cell_1_24_8 ASCII_cell_1_24_9 Synchronous IdleASCII_cell_1_24_10
001 0111ASCII_cell_1_25_0 027ASCII_cell_1_25_1 23ASCII_cell_1_25_2 17ASCII_cell_1_25_3 LEMASCII_cell_1_25_4 ETBASCII_cell_1_25_5 ASCII_cell_1_25_7 ^WASCII_cell_1_25_8 ASCII_cell_1_25_9 End of Transmission BlockASCII_cell_1_25_10
001 1000ASCII_cell_1_26_0 030ASCII_cell_1_26_1 24ASCII_cell_1_26_2 18ASCII_cell_1_26_3 S0ASCII_cell_1_26_4 CANASCII_cell_1_26_5 ASCII_cell_1_26_7 ^XASCII_cell_1_26_8 ASCII_cell_1_26_9 CancelASCII_cell_1_26_10
001 1001ASCII_cell_1_27_0 031ASCII_cell_1_27_1 25ASCII_cell_1_27_2 19ASCII_cell_1_27_3 S1ASCII_cell_1_27_4 EMASCII_cell_1_27_5 ASCII_cell_1_27_7 ^YASCII_cell_1_27_8 ASCII_cell_1_27_9 End of MediumASCII_cell_1_27_10
001 1010ASCII_cell_1_28_0 032ASCII_cell_1_28_1 26ASCII_cell_1_28_2 1AASCII_cell_1_28_3 S2ASCII_cell_1_28_4 SSASCII_cell_1_28_5 SUBASCII_cell_1_28_6 ASCII_cell_1_28_7 ^ZASCII_cell_1_28_8 ASCII_cell_1_28_9 SubstituteASCII_cell_1_28_10
001 1011ASCII_cell_1_29_0 033ASCII_cell_1_29_1 27ASCII_cell_1_29_2 1BASCII_cell_1_29_3 S3ASCII_cell_1_29_4 ESCASCII_cell_1_29_5 ASCII_cell_1_29_7 ^[ASCII_cell_1_29_8 \eASCII_cell_1_29_9 EscapeASCII_cell_1_29_10
001 1100ASCII_cell_1_30_0 034ASCII_cell_1_30_1 28ASCII_cell_1_30_2 1CASCII_cell_1_30_3 S4ASCII_cell_1_30_4 FSASCII_cell_1_30_5 ASCII_cell_1_30_7 ^\ASCII_cell_1_30_8 ASCII_cell_1_30_9 ASCII_cell_1_30_10
001 1101ASCII_cell_1_31_0 035ASCII_cell_1_31_1 29ASCII_cell_1_31_2 1DASCII_cell_1_31_3 S5ASCII_cell_1_31_4 GSASCII_cell_1_31_5 ASCII_cell_1_31_7 ^]ASCII_cell_1_31_8 ASCII_cell_1_31_9 Group SeparatorASCII_cell_1_31_10
001 1110ASCII_cell_1_32_0 036ASCII_cell_1_32_1 30ASCII_cell_1_32_2 1EASCII_cell_1_32_3 S6ASCII_cell_1_32_4 RSASCII_cell_1_32_5 ASCII_cell_1_32_7 ^^ASCII_cell_1_32_8 ASCII_cell_1_32_9 Record SeparatorASCII_cell_1_32_10
001 1111ASCII_cell_1_33_0 037ASCII_cell_1_33_1 31ASCII_cell_1_33_2 1FASCII_cell_1_33_3 S7ASCII_cell_1_33_4 USASCII_cell_1_33_5 ASCII_cell_1_33_7 ^_ASCII_cell_1_33_8 ASCII_cell_1_33_9 Unit SeparatorASCII_cell_1_33_10
111 1111ASCII_cell_1_34_0 177ASCII_cell_1_34_1 127ASCII_cell_1_34_2 7FASCII_cell_1_34_3 DELASCII_cell_1_34_4 ASCII_cell_1_34_7 ^?ASCII_cell_1_34_8 ASCII_cell_1_34_9 DeleteASCII_cell_1_34_10

Other representations might be used by specialist equipment, for example ISO 2047 graphics or hexadecimal numbers. ASCII_sentence_139

Printable characters ASCII_section_13

Codes 20hex to 7Ehex, known as the printable characters, represent letters, digits, punctuation marks, and a few miscellaneous symbols. ASCII_sentence_140

There are 95 printable characters in total. ASCII_sentence_141

Code 20hex, the "space" character, denotes the space between words, as produced by the space bar of a keyboard. ASCII_sentence_142

Since the space character is considered an invisible graphic (rather than a control character) it is listed in the table below instead of in the previous section. ASCII_sentence_143

Code 7Fhex corresponds to the non-printable "delete" (DEL) control character and is therefore omitted from this chart; it is covered in the previous section's chart. ASCII_sentence_144

Earlier versions of ASCII used the up arrow instead of the caret (5Ehex) and the left arrow instead of the underscore (5Fhex). ASCII_sentence_145

ASCII_table_general_2

BinaryASCII_header_cell_2_0_0 OctASCII_header_cell_2_0_1 DecASCII_header_cell_2_0_2 HexASCII_header_cell_2_0_3 GlyphASCII_header_cell_2_0_4
1963ASCII_header_cell_2_1_0 1965ASCII_header_cell_2_1_1 1967ASCII_header_cell_2_1_2
010 0000ASCII_cell_2_2_0 040ASCII_cell_2_2_1 32ASCII_cell_2_2_2 20ASCII_cell_2_2_3 spaceASCII_cell_2_2_4
010 0001ASCII_cell_2_3_0 041ASCII_cell_2_3_1 33ASCII_cell_2_3_2 21ASCII_cell_2_3_3 !ASCII_cell_2_3_4
010 0010ASCII_cell_2_4_0 042ASCII_cell_2_4_1 34ASCII_cell_2_4_2 22ASCII_cell_2_4_3 "ASCII_cell_2_4_4
010 0011ASCII_cell_2_5_0 043ASCII_cell_2_5_1 35ASCII_cell_2_5_2 23ASCII_cell_2_5_3 #ASCII_cell_2_5_4
010 0100ASCII_cell_2_6_0 044ASCII_cell_2_6_1 36ASCII_cell_2_6_2 24ASCII_cell_2_6_3 $ASCII_cell_2_6_4
010 0101ASCII_cell_2_7_0 045ASCII_cell_2_7_1 37ASCII_cell_2_7_2 25ASCII_cell_2_7_3 %ASCII_cell_2_7_4
010 0110ASCII_cell_2_8_0 046ASCII_cell_2_8_1 38ASCII_cell_2_8_2 26ASCII_cell_2_8_3 &ASCII_cell_2_8_4
010 0111ASCII_cell_2_9_0 047ASCII_cell_2_9_1 39ASCII_cell_2_9_2 27ASCII_cell_2_9_3 'ASCII_cell_2_9_4
010 1000ASCII_cell_2_10_0 050ASCII_cell_2_10_1 40ASCII_cell_2_10_2 28ASCII_cell_2_10_3 (ASCII_cell_2_10_4
010 1001ASCII_cell_2_11_0 051ASCII_cell_2_11_1 41ASCII_cell_2_11_2 29ASCII_cell_2_11_3 )ASCII_cell_2_11_4
010 1010ASCII_cell_2_12_0 052ASCII_cell_2_12_1 42ASCII_cell_2_12_2 2AASCII_cell_2_12_3 *ASCII_cell_2_12_4
010 1011ASCII_cell_2_13_0 053ASCII_cell_2_13_1 43ASCII_cell_2_13_2 2BASCII_cell_2_13_3 +ASCII_cell_2_13_4
010 1100ASCII_cell_2_14_0 054ASCII_cell_2_14_1 44ASCII_cell_2_14_2 2CASCII_cell_2_14_3 ,ASCII_cell_2_14_4
010 1101ASCII_cell_2_15_0 055ASCII_cell_2_15_1 45ASCII_cell_2_15_2 2DASCII_cell_2_15_3 -ASCII_cell_2_15_4
010 1110ASCII_cell_2_16_0 056ASCII_cell_2_16_1 46ASCII_cell_2_16_2 2EASCII_cell_2_16_3 .ASCII_cell_2_16_4
010 1111ASCII_cell_2_17_0 057ASCII_cell_2_17_1 47ASCII_cell_2_17_2 2FASCII_cell_2_17_3 /ASCII_cell_2_17_4
011 0000ASCII_cell_2_18_0 060ASCII_cell_2_18_1 48ASCII_cell_2_18_2 30ASCII_cell_2_18_3 0ASCII_cell_2_18_4
011 0001ASCII_cell_2_19_0 061ASCII_cell_2_19_1 49ASCII_cell_2_19_2 31ASCII_cell_2_19_3 1ASCII_cell_2_19_4
011 0010ASCII_cell_2_20_0 062ASCII_cell_2_20_1 50ASCII_cell_2_20_2 32ASCII_cell_2_20_3 2ASCII_cell_2_20_4
011 0011ASCII_cell_2_21_0 063ASCII_cell_2_21_1 51ASCII_cell_2_21_2 33ASCII_cell_2_21_3 3ASCII_cell_2_21_4
011 0100ASCII_cell_2_22_0 064ASCII_cell_2_22_1 52ASCII_cell_2_22_2 34ASCII_cell_2_22_3 4ASCII_cell_2_22_4
011 0101ASCII_cell_2_23_0 065ASCII_cell_2_23_1 53ASCII_cell_2_23_2 35ASCII_cell_2_23_3 5ASCII_cell_2_23_4
011 0110ASCII_cell_2_24_0 066ASCII_cell_2_24_1 54ASCII_cell_2_24_2 36ASCII_cell_2_24_3 6ASCII_cell_2_24_4
011 0111ASCII_cell_2_25_0 067ASCII_cell_2_25_1 55ASCII_cell_2_25_2 37ASCII_cell_2_25_3 7ASCII_cell_2_25_4
011 1000ASCII_cell_2_26_0 070ASCII_cell_2_26_1 56ASCII_cell_2_26_2 38ASCII_cell_2_26_3 8ASCII_cell_2_26_4
011 1001ASCII_cell_2_27_0 071ASCII_cell_2_27_1 57ASCII_cell_2_27_2 39ASCII_cell_2_27_3 9ASCII_cell_2_27_4
011 1010ASCII_cell_2_28_0 072ASCII_cell_2_28_1 58ASCII_cell_2_28_2 3AASCII_cell_2_28_3 :ASCII_cell_2_28_4
011 1011ASCII_cell_2_29_0 073ASCII_cell_2_29_1 59ASCII_cell_2_29_2 3BASCII_cell_2_29_3 ;ASCII_cell_2_29_4
011 1100ASCII_cell_2_30_0 074ASCII_cell_2_30_1 60ASCII_cell_2_30_2 3CASCII_cell_2_30_3 <ASCII_cell_2_30_4
011 1101ASCII_cell_2_31_0 075ASCII_cell_2_31_1 61ASCII_cell_2_31_2 3DASCII_cell_2_31_3 =ASCII_cell_2_31_4
011 1110ASCII_cell_2_32_0 076ASCII_cell_2_32_1 62ASCII_cell_2_32_2 3EASCII_cell_2_32_3 >ASCII_cell_2_32_4
011 1111ASCII_cell_2_33_0 077ASCII_cell_2_33_1 63ASCII_cell_2_33_2 3FASCII_cell_2_33_3 ?ASCII_cell_2_33_4
100 0000ASCII_cell_2_34_0 100ASCII_cell_2_34_1 64ASCII_cell_2_34_2 40ASCII_cell_2_34_3 @ASCII_cell_2_34_4 `ASCII_cell_2_34_5 @ASCII_cell_2_34_6
100 0001ASCII_cell_2_35_0 101ASCII_cell_2_35_1 65ASCII_cell_2_35_2 41ASCII_cell_2_35_3 AASCII_cell_2_35_4
100 0010ASCII_cell_2_36_0 102ASCII_cell_2_36_1 66ASCII_cell_2_36_2 42ASCII_cell_2_36_3 BASCII_cell_2_36_4
100 0011ASCII_cell_2_37_0 103ASCII_cell_2_37_1 67ASCII_cell_2_37_2 43ASCII_cell_2_37_3 CASCII_cell_2_37_4
100 0100ASCII_cell_2_38_0 104ASCII_cell_2_38_1 68ASCII_cell_2_38_2 44ASCII_cell_2_38_3 DASCII_cell_2_38_4
100 0101ASCII_cell_2_39_0 105ASCII_cell_2_39_1 69ASCII_cell_2_39_2 45ASCII_cell_2_39_3 EASCII_cell_2_39_4
100 0110ASCII_cell_2_40_0 106ASCII_cell_2_40_1 70ASCII_cell_2_40_2 46ASCII_cell_2_40_3 FASCII_cell_2_40_4
100 0111ASCII_cell_2_41_0 107ASCII_cell_2_41_1 71ASCII_cell_2_41_2 47ASCII_cell_2_41_3 GASCII_cell_2_41_4
100 1000ASCII_cell_2_42_0 110ASCII_cell_2_42_1 72ASCII_cell_2_42_2 48ASCII_cell_2_42_3 HASCII_cell_2_42_4
100 1001ASCII_cell_2_43_0 111ASCII_cell_2_43_1 73ASCII_cell_2_43_2 49ASCII_cell_2_43_3 IASCII_cell_2_43_4
100 1010ASCII_cell_2_44_0 112ASCII_cell_2_44_1 74ASCII_cell_2_44_2 4AASCII_cell_2_44_3 JASCII_cell_2_44_4
100 1011ASCII_cell_2_45_0 113ASCII_cell_2_45_1 75ASCII_cell_2_45_2 4BASCII_cell_2_45_3 KASCII_cell_2_45_4
100 1100ASCII_cell_2_46_0 114ASCII_cell_2_46_1 76ASCII_cell_2_46_2 4CASCII_cell_2_46_3 LASCII_cell_2_46_4
100 1101ASCII_cell_2_47_0 115ASCII_cell_2_47_1 77ASCII_cell_2_47_2 4DASCII_cell_2_47_3 MASCII_cell_2_47_4
100 1110ASCII_cell_2_48_0 116ASCII_cell_2_48_1 78ASCII_cell_2_48_2 4EASCII_cell_2_48_3 NASCII_cell_2_48_4
100 1111ASCII_cell_2_49_0 117ASCII_cell_2_49_1 79ASCII_cell_2_49_2 4FASCII_cell_2_49_3 OASCII_cell_2_49_4
101 0000ASCII_cell_2_50_0 120ASCII_cell_2_50_1 80ASCII_cell_2_50_2 50ASCII_cell_2_50_3 PASCII_cell_2_50_4
101 0001ASCII_cell_2_51_0 121ASCII_cell_2_51_1 81ASCII_cell_2_51_2 51ASCII_cell_2_51_3 QASCII_cell_2_51_4
101 0010ASCII_cell_2_52_0 122ASCII_cell_2_52_1 82ASCII_cell_2_52_2 52ASCII_cell_2_52_3 RASCII_cell_2_52_4
101 0011ASCII_cell_2_53_0 123ASCII_cell_2_53_1 83ASCII_cell_2_53_2 53ASCII_cell_2_53_3 SASCII_cell_2_53_4
101 0100ASCII_cell_2_54_0 124ASCII_cell_2_54_1 84ASCII_cell_2_54_2 54ASCII_cell_2_54_3 TASCII_cell_2_54_4
101 0101ASCII_cell_2_55_0 125ASCII_cell_2_55_1 85ASCII_cell_2_55_2 55ASCII_cell_2_55_3 UASCII_cell_2_55_4
101 0110ASCII_cell_2_56_0 126ASCII_cell_2_56_1 86ASCII_cell_2_56_2 56ASCII_cell_2_56_3 VASCII_cell_2_56_4
101 0111ASCII_cell_2_57_0 127ASCII_cell_2_57_1 87ASCII_cell_2_57_2 57ASCII_cell_2_57_3 WASCII_cell_2_57_4
101 1000ASCII_cell_2_58_0 130ASCII_cell_2_58_1 88ASCII_cell_2_58_2 58ASCII_cell_2_58_3 XASCII_cell_2_58_4
101 1001ASCII_cell_2_59_0 131ASCII_cell_2_59_1 89ASCII_cell_2_59_2 59ASCII_cell_2_59_3 YASCII_cell_2_59_4
101 1010ASCII_cell_2_60_0 132ASCII_cell_2_60_1 90ASCII_cell_2_60_2 5AASCII_cell_2_60_3 ZASCII_cell_2_60_4
101 1011ASCII_cell_2_61_0 133ASCII_cell_2_61_1 91ASCII_cell_2_61_2 5BASCII_cell_2_61_3 [ASCII_cell_2_61_4
101 1100ASCII_cell_2_62_0 134ASCII_cell_2_62_1 92ASCII_cell_2_62_2 5CASCII_cell_2_62_3 \ASCII_cell_2_62_4 ~ASCII_cell_2_62_5 \ASCII_cell_2_62_6
101 1101ASCII_cell_2_63_0 135ASCII_cell_2_63_1 93ASCII_cell_2_63_2 5DASCII_cell_2_63_3 Right_square_bracketASCII_cell_2_63_4
101 1110ASCII_cell_2_64_0 136ASCII_cell_2_64_1 94ASCII_cell_2_64_2 5EASCII_cell_2_64_3 ASCII_cell_2_64_4 ^ASCII_cell_2_64_5
101 1111ASCII_cell_2_65_0 137ASCII_cell_2_65_1 95ASCII_cell_2_65_2 5FASCII_cell_2_65_3 ASCII_cell_2_65_4 _ASCII_cell_2_65_5
110 0000ASCII_cell_2_66_0 140ASCII_cell_2_66_1 96ASCII_cell_2_66_2 60ASCII_cell_2_66_3 ASCII_cell_2_66_4 @ASCII_cell_2_66_5 `ASCII_cell_2_66_6
110 0001ASCII_cell_2_67_0 141ASCII_cell_2_67_1 97ASCII_cell_2_67_2 61ASCII_cell_2_67_3 ASCII_cell_2_67_4 aASCII_cell_2_67_5
110 0010ASCII_cell_2_68_0 142ASCII_cell_2_68_1 98ASCII_cell_2_68_2 62ASCII_cell_2_68_3 ASCII_cell_2_68_4 bASCII_cell_2_68_5
110 0011ASCII_cell_2_69_0 143ASCII_cell_2_69_1 99ASCII_cell_2_69_2 63ASCII_cell_2_69_3 ASCII_cell_2_69_4 cASCII_cell_2_69_5
110 0100ASCII_cell_2_70_0 144ASCII_cell_2_70_1 100ASCII_cell_2_70_2 64ASCII_cell_2_70_3 ASCII_cell_2_70_4 dASCII_cell_2_70_5
110 0101ASCII_cell_2_71_0 145ASCII_cell_2_71_1 101ASCII_cell_2_71_2 65ASCII_cell_2_71_3 ASCII_cell_2_71_4 eASCII_cell_2_71_5
110 0110ASCII_cell_2_72_0 146ASCII_cell_2_72_1 102ASCII_cell_2_72_2 66ASCII_cell_2_72_3 ASCII_cell_2_72_4 fASCII_cell_2_72_5
110 0111ASCII_cell_2_73_0 147ASCII_cell_2_73_1 103ASCII_cell_2_73_2 67ASCII_cell_2_73_3 ASCII_cell_2_73_4 gASCII_cell_2_73_5
110 1000ASCII_cell_2_74_0 150ASCII_cell_2_74_1 104ASCII_cell_2_74_2 68ASCII_cell_2_74_3 ASCII_cell_2_74_4 hASCII_cell_2_74_5
110 1001ASCII_cell_2_75_0 151ASCII_cell_2_75_1 105ASCII_cell_2_75_2 69ASCII_cell_2_75_3 ASCII_cell_2_75_4 iASCII_cell_2_75_5
110 1010ASCII_cell_2_76_0 152ASCII_cell_2_76_1 106ASCII_cell_2_76_2 6AASCII_cell_2_76_3 ASCII_cell_2_76_4 jASCII_cell_2_76_5
110 1011ASCII_cell_2_77_0 153ASCII_cell_2_77_1 107ASCII_cell_2_77_2 6BASCII_cell_2_77_3 ASCII_cell_2_77_4 kASCII_cell_2_77_5
110 1100ASCII_cell_2_78_0 154ASCII_cell_2_78_1 108ASCII_cell_2_78_2 6CASCII_cell_2_78_3 ASCII_cell_2_78_4 lASCII_cell_2_78_5
110 1101ASCII_cell_2_79_0 155ASCII_cell_2_79_1 109ASCII_cell_2_79_2 6DASCII_cell_2_79_3 ASCII_cell_2_79_4 mASCII_cell_2_79_5
110 1110ASCII_cell_2_80_0 156ASCII_cell_2_80_1 110ASCII_cell_2_80_2 6EASCII_cell_2_80_3 ASCII_cell_2_80_4 nASCII_cell_2_80_5
110 1111ASCII_cell_2_81_0 157ASCII_cell_2_81_1 111ASCII_cell_2_81_2 6FASCII_cell_2_81_3 ASCII_cell_2_81_4 oASCII_cell_2_81_5
111 0000ASCII_cell_2_82_0 160ASCII_cell_2_82_1 112ASCII_cell_2_82_2 70ASCII_cell_2_82_3 ASCII_cell_2_82_4 pASCII_cell_2_82_5
111 0001ASCII_cell_2_83_0 161ASCII_cell_2_83_1 113ASCII_cell_2_83_2 71ASCII_cell_2_83_3 ASCII_cell_2_83_4 qASCII_cell_2_83_5
111 0010ASCII_cell_2_84_0 162ASCII_cell_2_84_1 114ASCII_cell_2_84_2 72ASCII_cell_2_84_3 ASCII_cell_2_84_4 rASCII_cell_2_84_5
111 0011ASCII_cell_2_85_0 163ASCII_cell_2_85_1 115ASCII_cell_2_85_2 73ASCII_cell_2_85_3 ASCII_cell_2_85_4 sASCII_cell_2_85_5
111 0100ASCII_cell_2_86_0 164ASCII_cell_2_86_1 116ASCII_cell_2_86_2 74ASCII_cell_2_86_3 ASCII_cell_2_86_4 tASCII_cell_2_86_5
111 0101ASCII_cell_2_87_0 165ASCII_cell_2_87_1 117ASCII_cell_2_87_2 75ASCII_cell_2_87_3 ASCII_cell_2_87_4 uASCII_cell_2_87_5
111 0110ASCII_cell_2_88_0 166ASCII_cell_2_88_1 118ASCII_cell_2_88_2 76ASCII_cell_2_88_3 ASCII_cell_2_88_4 vASCII_cell_2_88_5
111 0111ASCII_cell_2_89_0 167ASCII_cell_2_89_1 119ASCII_cell_2_89_2 77ASCII_cell_2_89_3 ASCII_cell_2_89_4 wASCII_cell_2_89_5
111 1000ASCII_cell_2_90_0 170ASCII_cell_2_90_1 120ASCII_cell_2_90_2 78ASCII_cell_2_90_3 ASCII_cell_2_90_4 xASCII_cell_2_90_5
111 1001ASCII_cell_2_91_0 171ASCII_cell_2_91_1 121ASCII_cell_2_91_2 79ASCII_cell_2_91_3 ASCII_cell_2_91_4 yASCII_cell_2_91_5
111 1010ASCII_cell_2_92_0 172ASCII_cell_2_92_1 122ASCII_cell_2_92_2 7AASCII_cell_2_92_3 ASCII_cell_2_92_4 zASCII_cell_2_92_5
111 1011ASCII_cell_2_93_0 173ASCII_cell_2_93_1 123ASCII_cell_2_93_2 7BASCII_cell_2_93_3 ASCII_cell_2_93_4 {ASCII_cell_2_93_5
111 1100ASCII_cell_2_94_0 174ASCII_cell_2_94_1 124ASCII_cell_2_94_2 7CASCII_cell_2_94_3 ACKASCII_cell_2_94_4 ¬ASCII_cell_2_94_5 [[Vertical_bar|]]ASCII_cell_2_94_6
111 1101ASCII_cell_2_95_0 175ASCII_cell_2_95_1 125ASCII_cell_2_95_2 7DASCII_cell_2_95_3 ASCII_cell_2_95_4 }ASCII_cell_2_95_5
111 1110ASCII_cell_2_96_0 176ASCII_cell_2_96_1 126ASCII_cell_2_96_2 7EASCII_cell_2_96_3 ESCASCII_cell_2_96_4 [[Vertical_bar|]]ASCII_cell_2_96_5 ~ASCII_cell_2_96_6

Character set ASCII_section_14

Points which represented a different character in previous versions (the 1963 version and/or the 1965 draft) are shown boxed. ASCII_sentence_146

Points assigned since the 1963 version but otherwise unchanged are shown lightly shaded relative to their legend colours. ASCII_sentence_147

ASCII_table_general_3

ASCII (1977/1986)ASCII_table_caption_3
ASCII_header_cell_3_0_0 _0ASCII_header_cell_3_0_1 _1ASCII_header_cell_3_0_2 _2ASCII_header_cell_3_0_3 _3ASCII_header_cell_3_0_4 _4ASCII_header_cell_3_0_5 _5ASCII_header_cell_3_0_6 _6ASCII_header_cell_3_0_7 _7ASCII_header_cell_3_0_8 _8ASCII_header_cell_3_0_9 _9ASCII_header_cell_3_0_10 _AASCII_header_cell_3_0_11 _BASCII_header_cell_3_0_12 _CASCII_header_cell_3_0_13 _DASCII_header_cell_3_0_14 _EASCII_header_cell_3_0_15 _FASCII_header_cell_3_0_16
0_

0ASCII_header_cell_3_1_0

NUL

0000ASCII_cell_3_1_1

SOH

0001ASCII_cell_3_1_2

STX

0002ASCII_cell_3_1_3

ETX

0003ASCII_cell_3_1_4

EOT

0004ASCII_cell_3_1_5

ENQ

0005ASCII_cell_3_1_6

ACK

0006ASCII_cell_3_1_7

BEL

0007ASCII_cell_3_1_8

BS

0008ASCII_cell_3_1_9

HT

0009ASCII_cell_3_1_10

LF

000AASCII_cell_3_1_11

VT

000BASCII_cell_3_1_12

FF

000CASCII_cell_3_1_13

CR

000DASCII_cell_3_1_14

SO

000EASCII_cell_3_1_15

SI

000FASCII_cell_3_1_16

1_

16ASCII_header_cell_3_2_0

DLE

0010ASCII_cell_3_2_1

DC1

0011ASCII_cell_3_2_2

DC2

0012ASCII_cell_3_2_3

DC3

0013ASCII_cell_3_2_4

DC4

0014ASCII_cell_3_2_5

NAK

0015ASCII_cell_3_2_6

SYN

0016ASCII_cell_3_2_7

ETB

0017ASCII_cell_3_2_8

CAN

0018ASCII_cell_3_2_9

EM

0019ASCII_cell_3_2_10

SUB

001AASCII_cell_3_2_11

ESC

001BASCII_cell_3_2_12

001CASCII_cell_3_2_13 GS

001DASCII_cell_3_2_14

RS

001EASCII_cell_3_2_15

US

001FASCII_cell_3_2_16

2_

32ASCII_header_cell_3_3_0

SP

0020ASCII_cell_3_3_1

!

0021ASCII_cell_3_3_2

"

0022ASCII_cell_3_3_3

#

0023ASCII_cell_3_3_4

$

0024ASCII_cell_3_3_5

%

0025ASCII_cell_3_3_6

&

0026ASCII_cell_3_3_7

'

0027ASCII_cell_3_3_8

(

0028ASCII_cell_3_3_9

)

0029ASCII_cell_3_3_10

*

002AASCII_cell_3_3_11

+

002BASCII_cell_3_3_12

,

002CASCII_cell_3_3_13

-

002DASCII_cell_3_3_14

.

002EASCII_cell_3_3_15

/

002FASCII_cell_3_3_16

3_

48ASCII_header_cell_3_4_0

0

0030ASCII_cell_3_4_1

1

0031ASCII_cell_3_4_2

2

0032ASCII_cell_3_4_3

3

0033ASCII_cell_3_4_4

4

0034ASCII_cell_3_4_5

5

0035ASCII_cell_3_4_6

6

0036ASCII_cell_3_4_7

7

0037ASCII_cell_3_4_8

8

0038ASCII_cell_3_4_9

9

0039ASCII_cell_3_4_10

:

003AASCII_cell_3_4_11

;

003BASCII_cell_3_4_12

<

003CASCII_cell_3_4_13

=

003DASCII_cell_3_4_14

>

003EASCII_cell_3_4_15

?

003FASCII_cell_3_4_16

4_

64ASCII_header_cell_3_5_0

@

0040ASCII_cell_3_5_1

A

0041ASCII_cell_3_5_2

B

0042ASCII_cell_3_5_3

C

0043ASCII_cell_3_5_4

D

0044ASCII_cell_3_5_5

E

0045ASCII_cell_3_5_6

F

0046ASCII_cell_3_5_7

G

0047ASCII_cell_3_5_8

H

0048ASCII_cell_3_5_9

I

0049ASCII_cell_3_5_10

J

004AASCII_cell_3_5_11

K

004BASCII_cell_3_5_12

L

004CASCII_cell_3_5_13

M

004DASCII_cell_3_5_14

N

004EASCII_cell_3_5_15

O

004FASCII_cell_3_5_16

5_

80ASCII_header_cell_3_6_0

P

0050ASCII_cell_3_6_1

Q

0051ASCII_cell_3_6_2

R

0052ASCII_cell_3_6_3

S

0053ASCII_cell_3_6_4

T

0054ASCII_cell_3_6_5

U

0055ASCII_cell_3_6_6

V

0056ASCII_cell_3_6_7

W

0057ASCII_cell_3_6_8

X

0058ASCII_cell_3_6_9

Y

0059ASCII_cell_3_6_10

Z

005AASCII_cell_3_6_11

[

005BASCII_cell_3_6_12

\

005CASCII_cell_3_6_13

Right_square_bracket

005DASCII_cell_3_6_14

^

005EASCII_cell_3_6_15

_

005FASCII_cell_3_6_16

6_

96ASCII_header_cell_3_7_0

`

0060ASCII_cell_3_7_1

a

0061ASCII_cell_3_7_2

b

0062ASCII_cell_3_7_3

c

0063ASCII_cell_3_7_4

d

0064ASCII_cell_3_7_5

e

0065ASCII_cell_3_7_6

f

0066ASCII_cell_3_7_7

g

0067ASCII_cell_3_7_8

h

0068ASCII_cell_3_7_9

i

0069ASCII_cell_3_7_10

j

006AASCII_cell_3_7_11

k

006BASCII_cell_3_7_12

l

006CASCII_cell_3_7_13

m

006DASCII_cell_3_7_14

n

006EASCII_cell_3_7_15

o

006FASCII_cell_3_7_16

7_

112ASCII_header_cell_3_8_0

p

0070ASCII_cell_3_8_1

q

0071ASCII_cell_3_8_2

r

0072ASCII_cell_3_8_3

s

0073ASCII_cell_3_8_4

t

0074ASCII_cell_3_8_5

u

0075ASCII_cell_3_8_6

v

0076ASCII_cell_3_8_7

w

0077ASCII_cell_3_8_8

x

0078ASCII_cell_3_8_9

y

0079ASCII_cell_3_8_10

z

007AASCII_cell_3_8_11

{

007BASCII_cell_3_8_12

[[Vertical_bar|]]

007CASCII_cell_3_8_13

}

007DASCII_cell_3_8_14

~

007EASCII_cell_3_8_15

DEL

007FASCII_cell_3_8_16

Letter   Number   Punctuation   Symbol   Other   Undefined   Character changed from 1963 version and/or 1965 draft ASCII_sentence_148

Use ASCII_section_15

ASCII was first used commercially during 1963 as a seven-bit teleprinter code for American Telephone & Telegraph's TWX (TeletypeWriter eXchange) network. ASCII_sentence_149

TWX originally used the earlier five-bit ITA2, which was also used by the competing Telex teleprinter system. ASCII_sentence_150

Bob Bemer introduced features such as the escape sequence. ASCII_sentence_151

His British colleague Hugh McGregor Ross helped to popularize this work – according to Bemer, "so much so that the code that was to become ASCII was first called the Bemer–Ross Code in Europe". ASCII_sentence_152

Because of his extensive work on ASCII, Bemer has been called "the father of ASCII". ASCII_sentence_153

On March 11, 1968, U.S. President Lyndon B. Johnson mandated that all computers purchased by the United States Federal Government support ASCII, stating: ASCII_sentence_154

ASCII was the most common character encoding on the World Wide Web until December 2007, when UTF-8 encoding surpassed it; UTF-8 is backward compatible with ASCII. ASCII_sentence_155

Variants and derivations ASCII_section_16

As computer technology spread throughout the world, different standards bodies and corporations developed many variations of ASCII to facilitate the expression of non-English languages that used Roman-based alphabets. ASCII_sentence_156

One could class some of these variations as "ASCII extensions", although some misuse that term to represent all variants, including those that do not preserve ASCII's character-map in the 7-bit range. ASCII_sentence_157

Furthermore, the ASCII extensions have also been mislabelled as ASCII. ASCII_sentence_158

7-bit codes ASCII_section_17

Main articles: ECMA-6, ISO/IEC 646, and ITU T.50 ASCII_sentence_159

See also: UTF-7 ASCII_sentence_160

From early in its development, ASCII was intended to be just one of several national variants of an international character code standard. ASCII_sentence_161

Other international standards bodies have ratified character encodings such as ISO 646 (1967) that are identical or nearly identical to ASCII, with extensions for characters outside the English alphabet and symbols used outside the United States, such as the symbol for the United Kingdom's pound sterling (£). ASCII_sentence_162

Almost every country needed an adapted version of ASCII, since ASCII suited the needs of only the US and a few other countries. ASCII_sentence_163

For example, Canada had its own version that supported French characters. ASCII_sentence_164

Many other countries developed variants of ASCII to include non-English letters (e.g. é, ñ, ß, Ł), currency symbols (e.g. £, ¥), etc. See also YUSCII (Yugoslavia). ASCII_sentence_165

It would share most characters in common, but assign other locally useful characters to several code points reserved for "national use". ASCII_sentence_166

However, the four years that elapsed between the publication of ASCII-1963 and ISO's first acceptance of an international recommendation during 1967 caused ASCII's choices for the national use characters to seem to be de facto standards for the world, causing confusion and incompatibility once other countries did begin to make their own assignments to these code points. ASCII_sentence_167

ISO/IEC 646, like ASCII, is a 7-bit character set. ASCII_sentence_168

It does not make any additional codes available, so the same code points encoded different characters in different countries. ASCII_sentence_169

Escape codes were defined to indicate which national variant applied to a piece of text, but they were rarely used, so it was often impossible to know what variant to work with and, therefore, which character a code represented, and in general, text-processing systems could cope with only one variant anyway. ASCII_sentence_170

Because the bracket and brace characters of ASCII were assigned to "national use" code points that were used for accented letters in other national variants of ISO/IEC 646, a German, French, or Swedish, etc. programmer using their national variant of ISO/IEC 646, rather than ASCII, had to write, and thus read, something such as ASCII_sentence_171

ASCII_description_list_2

  • ä aÄiÜ = 'Ön'; üASCII_item_2_14

instead of ASCII_sentence_172

ASCII_description_list_3

  • { a[i] = '\n'; }ASCII_item_3_15

C trigraphs were created to solve this problem for ANSI C, although their late introduction and inconsistent implementation in compilers limited their use. ASCII_sentence_173

Many programmers kept their computers on US-ASCII, so plain-text in Swedish, German etc. (for example, in e-mail or Usenet) contained "{, }" and similar variants in the middle of words, something those programmers got used to. ASCII_sentence_174

For example, a Swedish programmer mailing another programmer asking if they should go for lunch, could get "N{ jag har sm|rg}sar" as the answer, which should be "Nä jag har smörgåsar" meaning "No I've got sandwiches". ASCII_sentence_175

8-bit codes ASCII_section_18

Main articles: Extended ASCII and ISO/IEC 8859 ASCII_sentence_176

See also: UTF-8 ASCII_sentence_177

Eventually, as 8-, 16- and 32-bit (and later 64-bit) computers began to replace 12-, 18- and 36-bit computers as the norm, it became common to use an 8-bit byte to store each character in memory, providing an opportunity for extended, 8-bit relatives of ASCII. ASCII_sentence_178

In most cases these developed as true extensions of ASCII, leaving the original character-mapping intact, but adding additional character definitions after the first 128 (i.e., 7-bit) characters. ASCII_sentence_179

Encodings include ISCII (India), VISCII (Vietnam). ASCII_sentence_180

Although these encodings are sometimes referred to as ASCII, true ASCII is defined strictly only by the ANSI standard. ASCII_sentence_181

Most early home computer systems developed their own 8-bit character sets containing line-drawing and game glyphs, and often filled in some or all of the control characters from 0 to 31 with more graphics. ASCII_sentence_182

Kaypro CP/M computers used the "upper" 128 characters for the Greek alphabet. ASCII_sentence_183

The PETSCII code Commodore International used for their 8-bit systems is probably unique among post-1970 codes in being based on ASCII-1963, instead of the more common ASCII-1967, such as found on the ZX Spectrum computer. ASCII_sentence_184

Atari 8-bit computers and Galaksija computers also used ASCII variants. ASCII_sentence_185

The IBM PC defined code page 437, which replaced the control characters with graphic symbols such as smiley faces, and mapped additional graphic characters to the upper 128 positions. ASCII_sentence_186

Operating systems such as DOS supported these code pages, and manufacturers of IBM PCs supported them in hardware. ASCII_sentence_187

Digital Equipment Corporation developed the Multinational Character Set (DEC-MCS) for use in the popular VT220 terminal as one of the first extensions designed more for international languages than for block graphics. ASCII_sentence_188

The Macintosh defined Mac OS Roman and Postscript also defined a set, both of these contained both international letters and typographic punctuation marks instead of graphics, more like modern character sets. ASCII_sentence_189

The ISO/IEC 8859 standard (derived from the DEC-MCS) finally provided a standard that most systems copied (at least as accurately as they copied ASCII, but with many substitutions). ASCII_sentence_190

A popular further extension designed by Microsoft, Windows-1252 (often mislabeled as ISO-8859-1), added the typographic punctuation marks needed for traditional text printing. ASCII_sentence_191

ISO-8859-1, Windows-1252, and the original 7-bit ASCII were the most common character encodings until 2008 when UTF-8 became more common. ASCII_sentence_192

ISO/IEC 4873 introduced 32 additional control codes defined in the 80–9F hexadecimal range, as part of extending the 7-bit ASCII encoding to become an 8-bit system. ASCII_sentence_193

Unicode ASCII_section_19

Main articles: Unicode and ISO/IEC 10646 ASCII_sentence_194

See also: Basic Latin (Unicode block) ASCII_sentence_195

Unicode and the ISO/IEC 10646 Universal Character Set (UCS) have a much wider array of characters and their various encoding forms have begun to supplant ISO/IEC 8859 and ASCII rapidly in many environments. ASCII_sentence_196

While ASCII is limited to 128 characters, Unicode and the UCS support more characters by separating the concepts of unique identification (using natural numbers called code points) and encoding (to 8-, 16- or 32-bit binary formats, called UTF-8, UTF-16 and UTF-32). ASCII_sentence_197

ASCII was incorporated into the Unicode (1991) character set as the first 128 symbols, so the 7-bit ASCII characters have the same numeric codes in both sets. ASCII_sentence_198

This allows UTF-8 to be backward compatible with 7-bit ASCII, as a UTF-8 file containing only ASCII characters is identical to an ASCII file containing the same sequence of characters. ASCII_sentence_199

Even more importantly, forward compatibility is ensured as software that recognizes only 7-bit ASCII characters as special and does not alter bytes with the highest bit set (as is often done to support 8-bit ASCII extensions such as ISO-8859-1) will preserve UTF-8 data unchanged. ASCII_sentence_200

See also ASCII_section_20

ASCII_unordered_list_4


Credits to the contents of this page go to the authors of the corresponding Wikipedia page: en.wikipedia.org/wiki/ASCII.