A mark of punctuation ( \ ) introduced in 1960 as a
deliberate way to convert two ALGOL symbols ("up" and "down" carets) into ASCII by using the new backslash and its traditional
opposite number, the virgule or slant ( / ):
\/ - or - /\ for example.
The backslash went on to find use in early UNIX programs and today is party of a typical QWERTY keyboard, usually
to the right of the bracket (and braces) keys. Other terms for the mark include slosh, reverse virgule, and reverse slash.
.