Non-deterministic finite automaton

A Non-deterministic Finite Automaton (NFA) is a theoretical model used to recognize patterns or sets of strings within formal languages. Unlike a deterministic automaton, where each step has a single clear path, an NFA can choose among multiple paths simultaneously, including transitions that don't depend on any input (epsilon moves). This means it can be in multiple states at once, exploring all possible options in parallel to determine if a string belongs to a language. If any of these paths lead to an accepting state, the NFA accepts the string. This flexibility makes NFAs useful for modeling complex pattern recognition tasks efficiently.