He thrusts his fist against the post, and still insists he sees the ghost.
~ The poem that helps Bill stop his stuttering.
William "Bill" Denbrough is the main protagonist of Stephen King's It. He is the leader of the Losers Club, ever since he lost his then-six-year-old brother George to the title adversary. He blamed himself for it, and his parents blamed him too. He became friends with the other members, who became his followers.
In the 1990 miniseries, he is played by Richard Thomas as an adult and the late Jonathan Brandis as a child. In the 2017 film, he is portrayed by Jaeden Lieberher as his younger self
Bill stutters when he speaks. The cause of this was most likely a car accident when he was little, but there is no proof of this.
Bill is constantly taunted by It, also known as Pennywise the Clown.