on my iMac, the Mail program (postage stamp symbol) is not set up. i dont want to make a .mac account. i use aol, gmail, and yahoo and i want to use one or all of those but i need to have .mac, IMAP, POP, or exchange, and i dont know what that means. my friend who has a Macbook (exactly like OSX but labtop) set up hers with yahoo mail or something, but deffinatly not .mac. does anyone know how to setup the mail app. without having a .mac account? whats POP, IMAP, and exchange? thank you!