How are questions chosen?

This is an awesome API, and am looking forward to using it.

Two questions:
a) Is it possible to request a new category?
b) When fetching questions, are they chosen at random or in some fixed order?

Thanks!

a)
Using the API you can select which category you want and get questions from that.

b)
It is chosen at random. If you don’t use a session token there’s a slim chance you get the same question if you generate different sets of questions. etc you generate 10 with the API then another 10.