In art Crosses are often associated with religion, and in particular Christianity. There are two obvious exceptions the Egyptian ankh cross and the swastika.
Owing to the fact that art is an important expression of religion, and due to the fact that religion has a propensity to diversify over time, there are also now a multitude of crosses. Here is a list that you can look up at your own leisure:
Ankh, avellan, calvary, celtic, cross clechée, cross-crosslet, cross fitché, cross fleury, cross formée, cross fourchée, cross gringolée, cross moline, cross pommée, Greek, Latin, Maltese, papal, patriarchal, potent, quadrate, St Andrew’s, tau and trefled.