Archive.org hosts many free and legal downloadable movies. BnWMovies.com also provide a download option. These direct download websites are generally limited to public domain movies. Alternatively, there are commercial streaming services, such as Hulu, that offer ad-supported streams of modern copyrighted movies.
Many ad-supported streaming services are available as alternatives to free direct download websites. DigitalTrends.com lists ad-supported streaming services for watching movies for free, including Crackle, Hulu, SnagFilms.
YouTube channels that specialize in public domain movies, such as BestPDMovies, provide a free and legal streaming option. However, it can be difficult to determine whether a movie is public domain or not, since some websites and uploaders mislabel pirated content as free and legal.