Admit it: you hadn't heard the word "fascinator" before Princess Beatrice made a meme out of her bowed Philip Treacy at the Royal Wedding. That's OK — the world of headwear is much more complex than you'd think. Sure, we were familiarized at an early age with The Cat in the Hat, but what hat did that cat begat? After all, hats are defined as "a generic term for headwear that usually includes a crown and a brim," but that's just the tip of the iceberg. It's time to put away your grade-school knowledge of hats and get an expert education.