Quantum mechanics determined?

Do truly "random" events occur at quantum level that can't be accurately predicted by the laws of physics?

Or just nobody understands how to yet?

Also could anyone recomend me an elementary text on quantum mechanics? (Something readable and interesting that goes over some of the maths involved too)

>>3
YES. That book is amazing. Griffiths is a great author.

>>1
As far as we can tell, yes, truly random events occur. Bell's inequalities show that there is no underlying hidden variable theory that predicts the indeterminism that arises from quantum mechanics. There are some loopholes though, so not everyone is sold on it yet, but the evidence is pretty convincing.

http://en.wikipedia.org/wiki/Bell%27s_theorem