bx-zone.com says :-
Automata comes from the Geek word ‘automaton’ the meaning of which is ‘self-making’. Automata theory throws light on the abstract machines. This theory is closely related to Automation where the primary components are the states and then the transitions from one state to another depending on the inputs received. Automata theory books are generally found in the closet of students studying computer science engineering as well as those studying IT engineering. Currently, in every smartphone while typing something in any editor, the operating system, whether ios or android, auto-suggests words for you. What is that? The theory behind auto-suggestion is natural language processing which evolves from the concepts of formal language and automata theory. In formal language theory, studies on syntactical aspects of a natural language happen as a result the algorithm constructs sentences using words formed by letters within a specific set of rules. I believe I have a whole lot of content to write on automate theory language and computation but I will restrict to mentioning that there are several books on introduction to automata theory on bx-zone.com, one of which is this one Automata, Computability and Complexity Theory and Applications right over here available at a discount of 37%. I would also like to mention that in order to crack exams of ISRO or get into NASA, a stronghold on this subject is a must.