settle this orgasm debate please!

So I was in art class today when my friends and I were talking. Conversations got a little more personal and we eventually got on the topic of orgasms. More people started asking questions. Somebody thought you can't cum without having an orgasm but others thought you can cum when you have sex or masturbate even if you haven't had an orgasm. What do you think? Please help settle this debate. We need answers.