If you own a few DVDs, you may find that some of them come with digital movie codes. These movie codes can be redeemed to get a digital version of the movie or swapped or sold for more digital movie codes. The DVD cover usually lists if there is a movie code inside or not. You can also redeem the digital copy of the movie on Google Play Movies.  To redeem your digital movie code on Google Play Movies, enter the promotional code on the redemption page to access the digital version of the movie. The movie will now be available to watch in your Google Play Movies app.