When exporting a movie, you choose a codec to compress the information for storage and transfer (such as on a DVD), and to decompress the information so it can be viewed again. The name “codec” comes from an abbreviation of its function of compression and decompression. During compression, repetitive and unnecessary information in the original file is discarded, causing the original file to lose information. For this reason, most codecs are considered lossy. Some codecs, though lossy, still allow the file to retain a high level of quality. The DV and MPEG codecs are especially good at maintaining excellent quality. Compressing video reduces its file size and data transfer rate, facilitating smooth playback and reducing storage requirements. A variety of codecs are available; no single codec is the best for all situations. For example, the best codec for compressing cartoon animation is generally not effective for compressing live‑action video. When you export from Premiere Elements, you generally only need to choose your medium of delivery and the application will select the optimal codec for you.
If you intend for your exported movie to be played back from a hard disk or CD, make sure that the codec you use to export your video is available to the audience for your movie. Most codecs for digital video and the web are already available on a majority of systems. However, if you are using a codec that’s native to a particular product, make sure that your target audience uses the same product, or can easily obtain the codec that you used.
If you intend to create a DVD or record to tape, codec compatibility is irrelevant. Your audience only needs to have the hardware necessary to play back the file.