Is there a library or a function that sends the email ?

I want to make my arduino conect via wifi and then send an email, the idea is very simple but the problem is that i've never worked with those protocols and stuffs, i just wanted something that's already premade, so i would just change the information.(if someone help me to understand, so i can make it myself, would be even greater).

P.S. IT'S A WIFI SHIELD AND NOT THE ETHERNET ONE.