What is the best rts game

The best RTS game ever is definitely the age of empires series. Although this may not be fact it is my honest opinion. There are 3 of them so far all of which have expansions. The first one is set in the day of the Egyptians and the Greeks and has a roman expansion. The second one is in medieval times and has a naive American expansion and the Third one is set in the colonisation of the Americas and has an Asian expansion and a native American expansion.