Amazing what you know

I have been thinking today isn't it amazing what you know.
I was talking to a friend on the phone about being able to do some of the work that I do and started to explain the ins and outs (as I understand it of licence and writer royalties). It was about half way through that she said it all was very complicated. I suddenly realised how much of what I know I take for granted as standard.
It suddenly made me think yep I know quite a bit, not in a big headed way just a sort of yep I can do this kind of way which the way my head has been the last 10 weeks (ie away with the fairies at times LOL) was very encouraging.
I suppose we all have knowledge and skills which to us seem standard until we meet someone who cant do it or doesn't know about it.
Just a ramble I just found it an eye opener for how much of what I know I don't think about at all while I'm doing my work.