If you're cynical, ASL is a way for people on the net to categorise you, depending on what it is they think a conversation with you will help them achieve.
If you're positive, it's a way of making sure they know they'll have something in common with you and that it's worth continuing to forge a friendship with you, and yes, it stands for "Age, Sex, Location".
As you already know, it's wise to think very long and hard before letting people in chat know anything about you. Of course.
