# ASCII

**ASCII** (**A**merican **S**tandard **C**ode for **I**nformation **I**nterchange) is an early character encoding standard that represents each character as a unique number between 0 and 127.

ASCII only **defines a limited set of characters**, including the English alphabet (**upper** and **lower** case), **numbers**, and a set of **common punctuation** and **control characters**.

## How it works ?

ASCII encoding assigns each character a unique 7-bit binary number. This allows each character to be represented as a single byte (8 bits) in memory.

Here is the entire ASCII table

| Decimal | Hexadecimal | Symbol                    |
| ------- | ----------- | ------------------------- |
| 0       | 00          | NUL (Null)                |
| 1       | 01          | SOH (Start Of Header)     |
| 2       | 02          | STX (Start Of Text)       |
| 3       | 03          | ETX (End of Text)         |
| 4       | 04          | EOT (End of Transmission) |
| 5       | 05          | ENQ (Enquiry)             |
| 6       | 06          | ACK (Acknowledge)         |
| 7       | 07          | BEL (Bell)                |
| 8       | 08          | BS (Backspace)            |
| 9       | 09          | HT (Horizontal tab)       |
| 10      | 0A          | LF (New Line)             |
| 11      | 0B          | VT (Vertical Tab)         |
| 12      | 0C          | FF (New Page)             |
| 13      | 0D          | CR (Carriage Return)      |
| 14      | 0E          | SO (Shift Out)            |
| 15      | 0F          | SI (Shift In)             |
| 16      | 10          | DLE (Data Link Escape)    |
| 17      | 11          | DC1 (Device control 1)    |
| 18      | 12          | DC2 (Device control 2)    |
| 19      | 13          | DC3 (Device control 3)    |
| 20      | 14          | DC4 (Device control 4)    |
| 21      | 15          | NAK (Negative Aknowledge) |
| 22      | 16          | SYN (Synchronous idle)    |
| 23      | 17          | ETB (End of trans. block) |
| 24      | 18          | CAN (Cancel)              |
| 25      | 19          | EM (End of Medium)        |
| 26      | 1A          | SUB (Substitute)          |
| 27      | 1B          | ESC (Escape)              |
| 28      | 1C          | FS (File separator)       |
| 29      | 1D          | GS (Group Separator)      |
| 30      | 1E          | RS (Record Separator)     |
| 31      | 1F          | US (Unit Separator)       |
| 32      | 20          | space                     |
| 33      | 21          | !                         |
| 34      | 22          | "                         |
| 35      | 23          | #                         |
| 36      | 24          | $                         |
| 37      | 25          | %                         |
| 38      | 26          | &                         |
| 39      | 27          | '                         |
| 40      | 28          | (                         |
| 41      | 29          | )                         |
| 42      | 2A          | \*                        |
| 43      | 2B          | +                         |
| 44      | 2C          | ,                         |
| 45      | 2D          | -                         |
| 46      | 2E          | .                         |
| 47      | 2F          | /                         |
| 48      | 30          | 0                         |
| 49      | 31          | 1                         |
| 50      | 32          | 2                         |
| 51      | 33          | 3                         |
| 52      | 34          | 4                         |
| 53      | 35          | 5                         |
| 54      | 36          | 6                         |
| 55      | 37          | 7                         |
| 56      | 38          | 8                         |
| 57      | 39          | 9                         |
| 58      | 3A          | :                         |
| 59      | 3B          | ;                         |
| 60      | 3C          | <                         |
| 61      | 3D          | =                         |
| 62      | 3E          | >                         |
| 63      | 3F          | ?                         |
| 64      | 40          | @                         |
| 65      | 41          | A                         |
| 66      | 42          | B                         |
| 67      | 43          | C                         |
| 68      | 44          | D                         |
| 69      | 45          | E                         |
| 70      | 46          | F                         |
| 71      | 47          | G                         |
| 72      | 48          | H                         |
| 73      | 49          | I                         |
| 74      | 4A          | J                         |
| 75      | 4B          | K                         |
| 76      | 4C          | L                         |
| 77      | 4D          | M                         |
| 78      | 4E          | N                         |
| 79      | 4F          | O                         |
| 80      | 50          | P                         |
| 81      | 51          | Q                         |
| 82      | 52          | R                         |
| 83      | 53          | S                         |
| 84      | 54          | T                         |
| 85      | 55          | U                         |
| 86      | 56          | V                         |
| 87      | 57          | W                         |
| 88      | 58          | X                         |
| 89      | 59          | Y                         |
| 90      | 5A          | Z                         |
| 91      | 5B          | \[                        |
| 92      | 5C          | \\                        |
| 93      | 5D          | ]                         |
| 94      | 5E          | ^                         |
| 95      | 5F          | \_                        |
| 96      | 60          | \`                        |
| 97      | 61          | a                         |
| 98      | 62          | b                         |
| 99      | 63          | c                         |
| 100     | 64          | d                         |
| 101     | 65          | e                         |
| 102     | 66          | f                         |
| 103     | 67          | g                         |
| 104     | 68          | h                         |
| 105     | 69          | i                         |
| 106     | 6A          | j                         |
| 107     | 6B          | k                         |
| 108     | 6C          | l                         |
| 109     | 6D          | m                         |
| 110     | 6E          | n                         |
| 111     | 6F          | o                         |
| 112     | 70          | p                         |
| 113     | 71          | q                         |
| 114     | 72          | r                         |
| 115     | 73          | s                         |
| 116     | 74          | t                         |
| 117     | 75          | u                         |
| 118     | 76          | v                         |
| 119     | 77          | w                         |
| 120     | 78          | x                         |
| 121     | 79          | y                         |
| 122     | 7A          | z                         |
| 123     | 7B          | {                         |
| 124     | 7C          | \|                        |
| 125     | 7D          | ]                         |
| 126     | 7E          | \~                        |
| 127     | 7F          | DEL                       |

There is an extended ASCII table that includes symbols till 255 :

| Decimal | Hexadecimal | Symbol |
| ------- | ----------- | ------ |
| 128     | 80          | €      |
| 129     | 81          |       |
| 130     | 82          | ‚      |
| 131     | 83          | ƒ      |
| 132     | 84          | „      |
| 133     | 85          | …      |
| 134     | 86          | †      |
| 135     | 87          | ‡      |
| 136     | 88          | ˆ      |
| 137     | 89          | ‰      |
| 138     | 8A          | Š      |
| 139     | 8B          | ‹      |
| 140     | 8C          | Π     |
| 141     | 8D          |       |
| 142     | 8E          | Ž      |
| 143     | 8F          |       |
| 144     | 90          |       |
| 145     | 91          | ‘      |
| 146     | 92          | ’      |
| 147     | 93          | “      |
| 148     | 94          | ”      |
| 149     | 95          | •      |
| 150     | 96          | –      |
| 151     | 97          | —      |
| 152     | 98          | ˜      |
| 153     | 99          | ™      |
| 154     | 9A          | š      |
| 155     | 9B          | ›      |
| 156     | 9C          | œ      |
| 157     | 9D          |       |
| 158     | 9E          | ž      |
| 159     | 9F          | Ÿ      |
| 160     | A0          |        |
| 161     | A1          | ¡      |
| 162     | A2          | ¢      |
| 163     | A3          | £      |
| 164     | A4          | ¤      |
| 165     | A5          | ¥      |
| 166     | A6          | ¦      |
| 167     | A7          | §      |
| 168     | A8          | ¨      |
| 169     | A9          | ©      |
| 170     | AA          | ª      |
| 171     | AB          | «      |
| 172     | AC          | ¬      |
| 173     | AD          | ­      |
| 174     | AE          | ®      |
| 175     | AF          | ¯      |
| 176     | B0          | °      |
| 177     | B1          | ±      |
| 178     | B2          | ²      |
| 179     | B3          | ³      |
| 180     | B4          | ´      |
| 181     | B5          | µ      |
| 182     | B6          | ¶      |
| 183     | B7          | ·      |
| 184     | B8          | ¸      |
| 185     | B9          | ¹      |
| 186     | BA          | º      |
| 187     | BB          | »      |
| 188     | BC          | ¼      |
| 189     | BD          | ½      |
| 190     | BE          | ¾      |
| 191     | BF          | ¿      |
| 192     | C0          | À      |
| 193     | C1          | Á      |
| 194     | C2          | Â      |
| 195     | C3          | Ã      |
| 196     | C4          | Ä      |
| 197     | C5          | Å      |
| 198     | C6          | Æ      |
| 199     | C7          | Ç      |
| 200     | C8          | È      |
| 201     | C9          | É      |
| 202     | CA          | Ê      |
| 203     | CB          | Ë      |
| 204     | CC          | Ì      |
| 205     | CD          | Í      |
| 206     | CE          | Î      |
| 207     | CF          | Ï      |
| 208     | D0          | Ð      |
| 209     | D1          | Ñ      |
| 210     | D2          | Ò      |
| 211     | D3          | Ó      |
| 212     | D4          | Ô      |
| 213     | D5          | Õ      |
| 214     | D6          | Ö      |
| 215     | D7          | ×      |
| 216     | D8          | Ø      |
| 217     | D9          | Ù      |
| 218     | DA          | Ú      |
| 219     | DB          | Û      |
| 220     | DC          | Ü      |
| 221     | DD          | Ý      |
| 222     | DE          | Þ      |
| 223     | DF          | ß      |
| 224     | E0          | à      |
| 225     | E1          | á      |
| 226     | E2          | â      |
| 227     | E3          | ã      |
| 228     | E4          | ä      |
| 229     | E5          | å      |
| 230     | E6          | æ      |
| 231     | E7          | ç      |
| 232     | E8          | è      |
| 233     | E9          | é      |
| 234     | EA          | ê      |
| 235     | EB          | ë      |
| 236     | EC          | ì      |
| 237     | ED          | í      |
| 238     | EE          | î      |
| 239     | EF          | ï      |
| 240     | F0          | ð      |
| 241     | F1          | ñ      |
| 242     | F2          | ò      |
| 243     | F3          | ó      |
| 244     | F4          | ô      |
| 245     | F5          | õ      |
| 246     | F6          | ö      |
| 247     | F7          | ÷      |
| 248     | F8          | ø      |
| 249     | F9          | ù      |
| 250     | FA          | ú      |
| 251     | FB          | û      |
| 252     | FC          | ü      |
| 253     | FD          | ý      |
| 254     | FE          | þ      |
| 255     | FF          | ÿ      |


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