It's National Superhero Day, which was created by Marvel in 1995.
Ranker.com has a list of the BEST comic book superheroes of all time. Over 130,000 people have voted. And this is a shock, but Superman did NOT make the top ten.
1. Spider-Man
2. Batman
3. Wolverine
4. Iron Man
5. Deadpool
6. Thor
7. Captain America
8. The Hulk
9. The Flash
10. Wonder Woman
Superman made the list at #11!!! 11? Really? I think he should've been much higher than that.