<character> "$", numeric character reference: "$", Common names: ITU-T: dollar sign. Rare: currency symbol; buck; cash; string; escape (when used as the echo of ASCII ESC); ding; cache; INTERCAL: big money.
Well-known uses of the dollar symbol in computing include as a prefix on the names of string variables in BASIC, shell and related languages like Perl. In shell languages it is also used in positional parameters so "$1" is the first parameter to a shell script, "$2" the second, etc. In a regular expression, $ matches the end of the string.