What's the difference between outbox and sentbox?

I have been trying to send pm out to people (almost wrote pms ) ) and most of the messages have been hitting my outbox, but I have a few older messages in my sentbox. What's the difference? Is mail in the sentbox actually messages that have been read by the receiver, or am I just doing something wrong?

Thanks!
Rich

no your right.....when you send someone a PM, it goes to the oubox until they have read it, at which point it goes to your sentbox D

Great thanks! Thought I was losing my mind for a second there.

well you're in the right place if you ever do D