A regular expression (usually called regex or regexp) is a sequence of characters that helps you search in text (strings). Various systems use Regex for field validation and for find-and-replace operations on text (strings). Regex is common in computer science. See Wikipedia Regex for more details.

Regex is used in Fotoware Alto Business Rules and field-format validations. Regex is best suited when you have a well-defined file-naming convention in place.