Eros itself is sometimes called infatuation, but I think it is much more than the word implies. The love of friends. This love is a love that exists because the lovers have a common topic of discussion outside of either of them. This love can easily be between more than two people, as well. Please do note that when I say the love of friends, I mean true friends, not the mere aquaintances that are called friends in modern English.
Friends often discuss things like true philosophy or religion.
The love of God. Agape is the very love, the true love. This is the love that christians have for their brethren. Agape wants to give because it is full and does not need. Agape does not need those it loves, but loves them almost precisely for that reason.