a Regular Expression , and gory details can be found by running 'man perlre'
a string that describes a pattern
a template of the pattern you wish to find
a tool for matching patterns in strings and replacing those matches with new content
Short for regular expression regexp is a pattern that denotes a set of strings, possibly an infinite set. For example, the regexp R.*xp matches any string starting with the letter and ending with the letters xp. In awk, regexps are used in patterns and in conditional expressions. Regexps may contain escape sequences. See section Regular Expressions as Patterns.
See `regular expression.'
a method to describe how to match a text string to a pattern. Some regular expressions can look rather complex (and some are) but this gives them great abilities. [ edit
