What is regular set?

A regular set, in the context of formal language theory, is a collection of strings that can be defined by a regular expression or recognized by a finite automaton. Regular sets include patterns that can be constructed using operations like union, concatenation, and Kleene star (which denotes repetition). They are fundamental in computer science, particularly in designing lexical analyzers and other language processing tools. Regular sets are characterized by their simplicity and efficiency in terms of computation and representation.