What does bonus time mean in live chess?

What does the bonus time mean; how is it figured?  How is this bonus enabled?

The bonus time is time added to your time after you make each move.

Thanks; for instance?

You will see time set like 15-0 meaning its a 15 minute game, if you see like 10-10 or 15-15, it a fifteen minute game with 15 minutes bonus time.  Once you make a move some time is added to you game.  It makes it a 30 minute maximum if it adds it all.   The computer figures and adds it.  I really dont know how it does it...

This helped me understand quite a bit: http://blog.chess.com/DrawMaster/how-to-calculate-the-effect-of-bonus-time

5-2 means for every single move,you get a addition of 2 seconds extra

Thank you for explaining :)

15-15 would mean you get 15 minutes on the clock at the start, but for every move you make you get a bonus 15 SECONDS.

The aim of this kind of time control is that you will always have at least 15 seconds to make a move.

Actually, it will. Read the above comments.

The computer on a chess site (I am not referring to dedicated chess engines, of course) can't tell a good move from a bad one.

Having read these conflicting views and dubious suggestions, I'm more confused than ever LOL

thanks. I've been enlightened.

Just ignore the post from knightspawn5, and ignore the (deleted)post of ranu204 that was quoted by blueemu.

The rest of the posts are correct.

Thanks guys , they really helped