Definition of Automaton:

An automaton is a mathematical model or an abstract machine that simulates and imitates the behavior of a system under study. It refers to any device that can perform a series of predetermined operations without human intervention.

Types of Automaton:

1. Finite Automaton (FA):

A finite automaton, also known as a finite state machine, is an abstract machine that operates on a limited or finite amount of memory. It consists of a set of states, a set of input symbols, a transition function, an initial state, and a set of final states.

2. Pushdown Automaton (PDA):

A pushdown automaton is an extension of the finite automaton with an added stack memory. It uses a stack to store and retrieve information, allowing it to recognize more complex languages than a finite automaton.

3. Turing Machine (TM):

A Turing machine is a theoretical computing device that can simulate any algorithmic process. It consists of a tape divided into cells, a read/write head to manipulate the tape, a set of states, and a transition function. Turing machines are capable of solving any problem that can be solved algorithmically.