What are the methods to encode Finite State Machines?
if you really need to understand it, you need to learn the theory behind it. Start with theory on formal languages. There you can find,that formal language can be specified by something called regular grammar, regular expressions or finite automaton (another name for finite state machine) etc. etc. Which are all basically the same thing with equal "computational power". 

So one answer to your question could be, that one method of encoding FSM is transformation of the FSM to a regular expression (which is basically textual string).