The backslash () is a typographical mark used mainly in computing and is the mirror image of the common slash (/). It is sometimes called a hack, whack…
2. C0 and C1 control codes
The C0 and C1 control code or control character sets define control codes for use in text by computer systems that use ASCII and derivatives of ASCII….
https://en.wikipedia.org/wiki/C0 and C1 control codes