Tumblr teaches me a lot about things I never knew that I needed to know. Not about English lit and so on (I had a surprisingly thorough education in that area), but the science side of tumblr taught me more than I would ever have thought possible.

Also quite a lot about how to interact with cats.

Or a commentary on the crappy education system in whatever country the commenter comes from.

If they aren’t taught Shakespeare or ancient history it’s possible they may not have learned about this event in history.