You've stayed through the movie's final credits -- a seemingly endless scrolling of mysterious job titles like best boy, grip, and Foley artist -- and if you're like many people, you have no idea what all these individuals do, or whether they're just strange names there to make the audience laugh. Well, all the jobs are real, and we'll get to them, along with gaffers, wranglers, and second second assistant directors, but first you need to know something about how the movie business operates.