Dirty deeds done dirt cheap.
Getting laid means you have casual sex with someone, or non-casual sex with someone you don't really care for. You would never said you got laid by someone you love.
The term is mostly used by guys, because most guys are insensitive pricks, but some girls use it too as some girls are insensitive pricks as well. It's mostly used for telling your friends the day after.
Guy: So, how did it go with the girl in the party last night?
Guy2: All the way
, dude. I got laid!
Guy: I just got laid, dude!
Guy3: You know, it kinda tells a lot about what you think about girls, the way you talk.