In modern society, movies popular all around the world. Movies have already became a industry since its birth at 1894, and produced thousand millions movies per year and earn huge profit. 
Why movies are so popular? I came up with two reasons, first, movies are a good entertainment for audience, second, as a form of art, films are also welcomed for its aesthetic value and ideology. 
As we can see in popular hollywood movie series like Superman, Spiderman, X-men, Batman, Pirate in Caribbean, Transformer, Harry Potter... It is not difficult to find that audiences can be easily attracted by special effects, engaging plots, exotic background and fantasy about superheroes and super powers. They provide us a world that we never experienced before, and show us what we would be dreaming in our dull lives--fictional fantastic world, beautiful heroes and heroines, romantic love stories. People use movies to gain an escape from stressful world of work and study. 
Another reason that I came up with is the art value of films. As a form of art, film is a manifestation of aesthetics. For instance, film photographing is a job on which photographer have to find the most beautiful or powerful way to show the moments. The quest for beauty is a kind of human nature, that's why we always enjoy something that can provide us with beautiful experiences. As a form of art, film also has the duty to inspire our thoughts as well as arouse our knowledge about the world. I can say couple of famous art film directors which were huge hits as those commercial movies I mentioned above, such as Ingmar Bergman, Tarkovsky, Akira Kurosawa and so on. 
I believe that movies would be more and more and more popular as its development on technology and thoughts.