has a bunch of names, like single quote
In C-based programming languages, this denotes a single character, like 'c', where c is any character.
In Perl, this denotes a string that should not translate any escaped codes.
In QuakeC, this indicates a vector, like 'x y z', where x, y, and z are the vector's components.
In several human languages, this is used for contractions, omitted letters, possession, and other things.
see also: " ‘ ’