control character

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun computing A character which does not have a direct visual appearance as a glyph, but rather causes some other display action to occur, such as a transition to a new line.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun ASCII characters to indicate carriage return or tab or backspace; typed by depressing a key and the control key at the same time