Answer: Stephen King's IT is a horror book about a clown who like's to eat kids and goes after a group if kids who call themselves the loser club. The thing about this clown is that he can change to whatever he wants, so in book he goes after all of the kids and goes to them as their worst fear/nightmare.
Explanation: Not really a explanation but there are 3 three movie out. one that came out with 1986, one that came 2017, and one that just came out this year in 2019.