ASCII Table and Description

ASCII stands for American Standard Code for Information Interchange. Computers can only understand numbers, so an ASCII code is the numerical representation of a character such as 'a' or '@' or an action of some sort. ASCII was developed a long time ago and now the non-printing characters are rarely used for their original purpose. Below is the ASCII character table and this includes descriptions of the first 32 non-printing characters. ASCII was actually designed for use with teletypes and so the descriptions are somewhat obscure. If someone says they want your CV however in ASCII format, all this means is they want 'plain' text with no formatting such as tabs, bold or underscoring - the raw format that any computer can understand. This is usually so they can easily import the file into their own applications without issues. Notepad.exe creates ASCII text, or in MS 

Binary	Oct	Dec	Hex	Abbr	[t 1]	[t 2]	[t 3]	Description
000 0000	000	0	00	NUL	␀	^@	\0	Null character
000 0001	001	1	01	SOH	␁	^A		Start of Header
000 0010	002	2	02	STX	␂	^B		Start of Text
000 0011	003	3	03	ETX	␃	^C		End of Text
000 0100	004	4	04	EOT	␄	^D		End of Transmission
000 0101	005	5	05	ENQ	␅	^E		Enquiry
000 0110	006	6	06	ACK	␆	^F		Acknowledgment
000 0111	007	7	07	BEL	␇	^G	\a	Bell
000 1000	010	8	08	BS	␈	^H	\b	Backspace[t 4][t 5]
000 1001	011	9	09	HT	␉	^I	\t	Horizontal Tab[t 6]
000 1010	012	10	0A	LF	␊	^J	\n	Line feed
000 1011	013	11	0B	VT	␋	^K	\v	Vertical Tab
000 1100	014	12	0C	FF	␌	^L	\f	Form feed
000 1101	015	13	0D	CR	␍	^M	\r	Carriage return[t 7]
000 1110	016	14	0E	SO	␎	^N		Shift Out
000 1111	017	15	0F	SI	␏	^O		Shift In
001 0000	020	16	10	DLE	␐	^P		Data Link Escape
001 0001	021	17	11	DC1	␑	^Q		Device Control 1 (oft. XON)
001 0010	022	18	12	DC2	␒	^R		Device Control 2
001 0011	023	19	13	DC3	␓	^S		Device Control 3 (oft. XOFF)
001 0100	024	20	14	DC4	␔	^T		Device Control 4
001 0101	025	21	15	NAK	␕	^U		Negative Acknowledgement
001 0110	026	22	16	SYN	␖	^V		Synchronous idle
001 0111	027	23	17	ETB	␗	^W		End of Transmission Block
001 1000	030	24	18	CAN	␘	^X		Cancel
001 1001	031	25	19	EM	␙	^Y		End of Medium
001 1010	032	26	1A	SUB	␚	^Z		Substitute
001 1011	033	27	1B	ESC	␛	^[	\e[t 8]	Escape[t 9]
001 1100	034	28	1C	FS	␜	^\		File Separator
001 1101	035	29	1D	GS	␝	^]		Group Separator
001 1110	036	30	1E	RS	␞	^^[t 10]		Record Separator
001 1111	037	31	1F	US	␟	^_		Unit Separator
111 1111	177	127	7F	DEL	␡	^?		Delete[t 11][t 5]

1. ^ The Unicode characters from the area U+2400 to U+2421 reserved for representing control characters when it is necessary to print or display them rather than have them perform their intended function. Some browsers may not display these properly.
2. ^ Caret notation often used to represent control characters. This also indicates the key sequence to input the character traditionally on most text terminals: The caret (^) that begins these sequences represents holding down the "Ctrl" key while typing the second character.
3. ^ Character Escape Codes in C programming language and many other languages influenced by it, such as Java and Perl (though not all implementations necessarily support all escape codes).
4. ^ The Backspace character can also be entered by pressing the "Backspace", "Bksp", or ← key on some systems.
5. ^ ^a b The ambiguity of Backspace is due to early terminals designed assuming the main use of the keyboard would be to manually punch paper tape while not connected to a computer. To delete the previous character you had to back up the paper tape punch, which for mechanical and simplicity reasons was a button on the punch itself and not the keyboard, then type the rubout character. They therefore placed a key producing rubout at the location used on typewriters for backspace. When systems used these terminals and provided command-line editing, they had to use the "rubout" code to perform a backspace, and often did not interpret the backspace character (they might echo "^H" for backspace). Other terminals not designed for paper tape made the key at this location produce Backspace, and systems designed for these used that character to back up. Since the delete code often produced a backspace effect, this also forced terminal manufacturers to make any "Delete" key produce something other than the Delete character.
6. ^ The Tab character can also be entered by pressing the "Tab" key on most systems.
7. ^ The Carriage Return character can also be entered by pressing the "Return", "Ret", "Enter", or ↵ key on most systems.
8. ^ The '\e' escape sequence is not part of ISO C and many other language specifications. However, it is understood by several compilers.
9. ^ The Escape character can also be entered by pressing the "Escape" or "Esc" key on some systems.
10. ^ ^^ means Control-Caret (pressing the "Ctrl" and "^" keys), not Control-Control.
11. ^ The Delete character can sometimes be entered by pressing the "Backspace", "Bksp", or ← key on some systems.

[edit]ASCII printable characters

Codes 0x21 to 0x7E, known as the printable characters, represent letters, digits, punctuation marks, and a few miscellaneous symbols.

Code 0x20, the space character, denotes the space between words, as produced by the space-bar of a keyboard. Since the space character is considered an invisible graphic (rather than a control character)^[8] and thus would not normally be visible, it is represented here by Unicode character U+2420 "␠"; Unicode characters U+2422 "␢" or U+2423 "␣" are also available for use when a visible representation of a space is necessary.

Code 0x7F 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.

Binary Oct Dec Hex Glyph 010 0000 040 32 20 ␠ 010 0001 041 33 21 ! 010 0010 042 34 22 " 010 0011 043 35 23 # 010 0100 044 36 24 $ 010 0101 045 37 25 % 010 0110 046 38 26 & 010 0111 047 39 27 ' 010 1000 050 40 28 ( 010 1001 051 41 29 ) 010 1010 052 42 2A * 010 1011 053 43 2B + 010 1100 054 44 2C , 010 1101 055 45 2D - 010 1110 056 46 2E . 010 1111 057 47 2F / 011 0000 060 48 30 0 011 0001 061 49 31 1 011 0010 062 50 32 2 011 0011 063 51 33 3 011 0100 064 52 34 4 011 0101 065 53 35 5 011 0110 066 54 36 6 011 0111 067 55 37 7 011 1000 070 56 38 8 011 1001 071 57 39 9 011 1010 072 58 3A : 011 1011 073 59 3B ; 011 1100 074 60 3C < 011 1101 075 61 3D = 011 1110 076 62 3E > 011 1111 077 63 3F ?

Binary Oct Dec Hex Glyph 100 0000 100 64 40 @ 100 0001 101 65 41 A 100 0010 102 66 42 B 100 0011 103 67 43 C 100 0100 104 68 44 D 100 0101 105 69 45 E 100 0110 106 70 46 F 100 0111 107 71 47 G 100 1000 110 72 48 H 100 1001 111 73 49 I 100 1010 112 74 4A J 100 1011 113 75 4B K 100 1100 114 76 4C L 100 1101 115 77 4D M 100 1110 116 78 4E N 100 1111 117 79 4F O 101 0000 120 80 50 P 101 0001 121 81 51 Q 101 0010 122 82 52 R 101 0011 123 83 53 S 101 0100 124 84 54 T 101 0101 125 85 55 U 101 0110 126 86 56 V 101 0111 127 87 57 W 101 1000 130 88 58 X 101 1001 131 89 59 Y 101 1010 132 90 5A Z 101 1011 133 91 5B [ 101 1100 134 92 5C \ 101 1101 135 93 5D ] 101 1110 136 94 5E ^ 101 1111 137 95 5F _

Binary Oct Dec Hex Glyph 110 0000 140 96 60 ` 110 0001 141 97 61 a 110 0010 142 98 62 b 110 0011 143 99 63 c 110 0100 144 100 64 d 110 0101 145 101 65 e 110 0110 146 102 66 f 110 0111 147 103 67 g 110 1000 150 104 68 h 110 1001 151 105 69 i 110 1010 152 106 6A j 110 1011 153 107 6B k 110 1100 154 108 6C l 110 1101 155 109 6D m 110 1110 156 110 6E n 110 1111 157 111 6F o 111 0000 160 112 70 p 111 0001 161 113 71 q 111 0010 162 114 72 r 111 0011 163 115 73 s 111 0100 164 116 74 t 111 0101 165 117 75 u 111 0110 166 118 76 v 111 0111 167 119 77 w 111 1000 170 120 78 x 111 1001 171 121 79 y 111 1010 172 122 7A z 111 1011 173 123 7B { 111 1100 174 124 7C | 111 1101 175 125 7D } 111 1110 176 126 7E ~

Extended ASCII Codes