I've read The Lord of the Rings trilogy plus The Hobbit, but there was one Tolkien bridge too far for me: The Silmarillion, the vast prequel/bible/collection of stories that only deep LOTR nerds have actually processed. Well, guess what -- C.G.P. Grey has done the required reading and created a five-minute video explaining the detailed mythology behind the books.

You might ask, Why does this matter? I'd respond: This video explains what the heck the wizards are, what the Balrog is (was?), and why humans have the "gift" of mortality...plus a lot more. I was surprised about how little I knew about the details (for instance, are the wizards human? Could any human train to become a wizard?); I always just kinda let it go by. If you care at all about the books or the movies, watch this:

Also highly relevant is this video's Reddit comment thread.