Kleene star

The Kleene star is an operation used in computer science and mathematics to describe all possible repeated combinations of a set of things, including doing nothing. For example, if you have a set of symbols like {a, b}, applying the Kleene star results in all strings made by combining 'a' and 'b' in any order and any number of times — including the empty string (no symbols). It’s a way to represent endless sequences built from a specific set, crucial in defining patterns and languages in automata theory and regular expressions.