Dexter: Yes, yes. She was quite a boat, the True Love, wasn't she?
Tracy: Was, and is.
Dexter: My, she was yar.
- Cary Grant and Katherine Hepburn in The Philadelphia Story
An exclamaition of agreement (and also used as a random exlamaition) often used by "pirates," but since pirates have now become "illegal downloaders of software/music" and those "pirates" tend to be teenagers, "yar!" is basically an exclamaition of agreement (and also used as a random exlamaition)often used by teenagers.