(covers information from several alternate timelines)
Hollywood was a district within Los Angeles, California, on the western coast of the North American continent on Earth. The district was most associated with the American film and television industry due to the presence of numerous movie studios, where many movies and television shows were filmed.
In an alternate timeline 1944, a German SS officer claimed that Americans were good at making Hollywood movies with stars like Betty Grable, Rita Hayworth and Veronica Lake, but not at fighting. He said that, at some point, he would go to Hollywood and meet Betty Grable. Jonathan Archer did not think that he was Grable's type. (ENT: "Storm Front")
In 2375, Tom Paris realized that something was wrong when he found Constance Goodheart's dead body in his holonovel The Adventures of Captain Proton. As he informed Tuvok, the good guys were never killed in 1930s Hollywood. (VOY: "Bride of Chaotica!")