Just a different way of saying "the shit" or "awesome." Where'd it come from you ask? It seems random you say? Well sir, I pulled it out of my ass.

It’s an acronym standing for Can’t Remember A Fucking Thing. It’s usually used to describe embarrassment at being unable to remember someone (CRAFT moment); going onstage as the lead in the latest theatrical performance and your mind goes completely blank (CRAFT situation); the next morning after a night when you got pissed as a fart and woke up in bed cuddling a traffic cone and a string of fairy lights wound round your prick.

To beat up or kill someone.

After finishing having sex with a girl you pull off the condom and throw it hitting her in the face hard enough to spladder cum all over her face making her look like a buttered buscuit

An expression of greatness. What you are talking about is really good, awesome if you will.

it means to commit suicide, just like in the song watcha say remix feat. loon