The '''automaton''', which is sometimes used interchangably with '''machine''', is one of the basic models of computation:
   * [Turing machine]
   * [Finite state machine]
   * [Deterministic finite state machine]
   * …
It can also be used as a powerful '''control structure''', transcending the block-hierarchical paradigm of ''structured programming'':
   * [A tiny state machine]
   * [Finite state machines]
   * [Automata in Tcl]
   * [Goto in Tcl]
   * [expect] command
   * …
The need for such power is most often felt when parsing or doing [IPC].

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[AM] (19 july 2010) Quite apart from the above, automata are also studied as mathematical objects - see the book A New kind of Science by Stephen Wolfram for instance (http://www.wolframscience.com/thebook.html). Here is one example: [A simple program with complex behaviour] 

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