The first 3 Star Wars films were the first full length novels in the Star Wars universe, and this was then followed by further books by Authors like Alan Dean Foster. More recently, a new line of novels were launched, featuring original stories set after the events of the Return of the Jedi. There is still a growing number of these novels, and many series, taking the stories and main characters years into the future (like Han and Leia getting married and having kids etc).