Are hook sizes In the US different than here in the UK?

I read about people tying on size 22's or even size 26's. They must be minute. I have some size 22 hooks I use for catching roach or rudd. But I have to get my grandson to tie them on the line for me they are so small. I could not imagine tying a fly on them. I doubt if there will be room. I am assuming your hooks are bigger than ours.......... unless you tell me otherwise.