In French, the passé composé is a compound tense that uses "être" as the auxiliary verb with certain verbs that generally indicate movement or a change of state. Here is a list of common verbs that use "être" in the passé composé:
aller (to go)
venir (to come)
arriver (to arrive)
partir (to leave)
entrer (to enter)
sortir (to go out)
monter (to go up)
descendre (to go down)
naître (to be born)
mourir (to die)
rester (to stay)
retourner (to return)
tomber (to fall)
passer (to pass by)
demeurer (to remain)