which may exhibit my ignorance. I got a B at IT A Level don'cha know.

How do wireless routers decide* who gets what bandwidth? If you've got ok performing 2mb broadband and, for example, two people are both downloading torrents which, given a faster connection (or one person turning their pc off) would reach pretty much maximum speed (say 8 or 9 hundred kb/s), how does it decide* who gets a speed of 500ish and who gets 300? or does it? Or something. Explain for me and/or point me to a link which explains where I've gone wrong. Thanks.

*Of course they don't decide, they aren't conscious entities. But you get what I mean. Hopefully.