What is FAQ Category for?

Yes, the FAQ category should be a good reference of FAQ's and their answers.

But it is reliant on people using the right categories to start with and the admins noticing when something has been posted in FAQ that perhaps shouldn't be there. I'd be happy to 'promote' any of our regular users here to help curate the content - let me know if you'd like to help do that and I'll go figure out how to do it.

And to answer your question directly, this post describes the category - About the FAQs category - if you have any updates to that I'll be happy to consider them.