It gets a little weird. The original Clarke story had the Discovery going to Saturn. Then the movie changed it to Jupiter. Then the movie was a big enough hit that Clarke wrote 2010 as a sequel to the movie with the action taking place around Jupiter. Which, while remaining around Jupiter, got changed some more when the book 2010 got adapted to make another movie.
There's also a third and fourth book in the series, 2061 and 3001.