cancel character

{{short description|Either of two control codes used to delete or rescind preceding data or characters}}

In telecommunications and character encoding, the term cancel character refers to a control character which may be either of:

1. "CAN", "Cancel", U+0018, or ^X used to indicate that the data with which it is associated are in error or are to be disregarded. Exact meaning can depend on protocol. For example:
2. * In some journalistic text transmission formats, it signifies that the preceding word should be deleted; it is sometimes called "Kill Word" ("KW") in this context.{{cite iso-ir |number=26 |title=Control set for newspaper text transmission |sponsor=International Press Telecommunications Council |sponsor-link=International Press Telecommunications Council |date=1976-03-25}}
3. * In some Videotex formats, it stops any running macros.{{cite iso-ir |number=132 |date=1987-07-31 |title=Primary Control Set of Data Syntax I of CCITT Rec. T.101 |sponsor=CCITT |sponsor-link=ITU-T}}{{cite iso-ir |number=135 |date=1987-07-31 |title=Primary Control Set of Data Syntax III of CCITT Rec. T.101 |sponsor=CCITT |sponsor-link=ITU-T}} In others, it clears the current line after the cursor position (compare {{control code link|EL}}).{{cite iso-ir |number=134 |date=1987-07-31 |title=Primary Control Set of Data Syntax II of CCITT Rec. T.101 |sponsor=CCITT |sponsor-link=ITU-T}}
4. "CCH", "Cancel Character", U+0094, or ESC T used to erase the previous character. This character was created as an unambiguous alternative to the much more common backspace character ("BS", U+0008), which has a now mostly obsolete alternative function of causing the following character to be superimposed on the preceding one.