trying to understand bitwise operations

[canderoc]

I come across a lot of bitwise operators when I look at the functions included in QM. So, I read about Bitwise operation on Wikipedia and understand how bitwise operators work on binary numbers, but I still don't understand how they work on variables and values in QM. For example, could some one tell me how to understand things like: if(flags&2=0). Is that the same as if(flags=2) ? If not, how do they differ?
Thanks