Information

Delete key can't be technically called a part of the C0 control character range. Initially it was used in order to designate previously erased characters on paper tape, because any character could be changed to all ones by punching holes in any place. On VT100 compatible terminals, this is the character produced by the key marked ⌫ . On modern machines it is called backspace and doesn't match the PC delete key.

Sometimes the delete character is also called a rubout. In computing it is the last character in the ASCII repertoire, having the code of 127 (decimal). Being a control character instead of a graphic one, in caret notation it's designated as ^? and has a graphic representation of ␡ in Unicode (because all ASCII control characters have their own graphic representations).

On modern systems terminal emulators it usually turn keys designated as "Delete" or "Del" into an escape sequence like ^~. Terminal emulators may produce DEL when ← Backspace key or Control+← Backspace or Control+? are being typed. Some other programs, for example Notepad insert this character using the same keys.

History

Initially this code was used in order to mark the characters that were deleted on punched tape, because any character could be changed to all ones just by punching holes in any place. In cases, when a character was punched mistakenly, punching out all seven bits made this position to be ignored or even deleted, a computer version of correction fluid. In hexadecimal, this is 7F to rubout 7 bits, and FF to rubout 8 bits. Lines were usually ended up by the three characters CR, LF, and rubout for teleprinters, for example Teletype Model 33. The rubout left some time in order for the print mechanism to physically move to the left margin. On VT100 compatible terminals, the Delete key generated this character. It transmits a delete character (octal 177, hexadecimal 7F) to the host system. On VT510 compatible terminals, this character is generated by the key designated ?, On modern machines it is commonly called backspace, and doesn't match the PC "Delete" key.

Current use

Unix-like operating systems are widely used it in the role of the clean up control character. In plain words, it's function is to delete the previous character in the line mode. However, it differs from its initial function where this code physically replaced characters on a punched tape to be deleted.

Unlike Unix, DOS/Windows haven't even tried to use this character in any function. Instead of it, Windows used backspace (0x08, or control-H) in order to delete the previous character. EGA/VGA fonts, being fonts that are used by Win32 console, usually have the "house" symbol ⌂ at 127 (0x7F) code point (see Code page 437 for details). Nevertheless, the heritage of it can be seen in some applications that can be considered as a part of the Windows operating system. Let's see an example: typing the Control and ← Backspace key combination in Microsoft Notepad will product the delete character.

Hash

MD5 Delete character

SHA256 Delete character

Base64 Delete character

• ← Previous char '~', code: 126

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