Editing Control key (section)

===ASCII control character entry===
The classic purpose of the control key is to generate ASCII control characters. ASCII control characters are those codes from 0 (0x0) to 31 (0x1F) which exist for various in-band signalling and display control purposes instead of for character display. The only codes typically used today are 3 (0x03) for [[enter key (Macintosh)|enter]] (on Macintosh computers, distinct from [[return key|return]]), 8 (0x08) for backspace, 9 (0x09) for horizontal tab, 10 (0x0A) for line break (newline on UNIX and Linux), 13 (0x0D) for carriage return (newline on older Mac systems), and 27 (0x1B) for escape.

ASCII control characters can be entered on Latin alphabet keyboards by holding the control key, and pressing the letter of the basic Latin alphabet whose 1-based position corresponds with the character. For example, some computers will issue an audible alert ("bell") if ctrl+G is pressed, as G is the 7th character of the basic Latin alphabet, and ASCII 7 (0x07) is the code for an audible bell to be rung on a teletype, later generalised to an audible tone of some kind emitted from the console. Many systems accept ctrl+M instead of the return key, for example you can type "dir" followed by ctrl+M instead of return to list the current directory at the Windows command prompt. ASCII codes outside of the range 1-26 use symbols: the escape character is ctrl+[, and some computers accept ctrl-@ for code 0 (NULL).

[[Category:Modifier keys]]