In computing, regular expressions provide a concise and flexible means for identifying strings of text of
interest, such as particular characters, words, or patterns of characters. Regular expressions
(abbreviated as regex or regexp, with plural forms regexes, regexps, or regexen) are written in a
formal language that can be interpreted by a regular expression processor, a program that either serves
as a parser generator or examines text and identifies parts
that match the provided specification. [see
wikipedia.org]
