Transition systems a transition systems is a tuple A =<S, So, T,a, B> where o sis a finite or infinite set of states o Is initial location o T is a finite or infinite set of transitions o a and B are two mapping from Tto S which take each transition t in Tto the two states a(t)and b(t, respectively the source and the target of the transition t a transition t with some source s and target s is ritten t:s→s’ Several transitions can have the same source and target a transition system is finite if s and Tare finiteTransition systems ◼ A transition systems is a tuple 𝒜 =< 𝑆, 𝑆0, 𝑇, 𝛼, 𝛽 > where  S is a finite or infinite set of states,  𝑆0 is initial location  T is a finite or infinite set of transitions,  𝛼 and 𝛽 are two mapping from T to S which take each transition t in T to the two states 𝛼(𝑡) and 𝛽(𝑡), respectively the source and the target of the transition t. ◼ A transition t with some source s and target s’ is written t : s→s’. ◼ Several transitions can have the same source and target. ◼ A transition system is finite if S and T are finite