I had no idea Claude Skills existed until today, can someone give me a plain English explanation?

I have been using Claude for a few months now for work tasks, and I only just stumbled across something called Claude Skills in a blog post.

I went looking for it in my settings and could not find anything obvious. Is this a separate feature I need to enable?

What does it actually do differently from just chatting with Claude normally? Would love a simple explanation before I go down a rabbit hole.