The term codec, a mashup of “compression” and “decompression,” refers to the way your camera saves video footage. Many DSLRs use the H.264/MPEG-4 AVC codec with an MOV container. With this combo, you should be able to use modern video editing software without converting to another file format. Sony and Panasonic use the AVCHD format, which is more efficient in terms of storage space and image quality, but it uses a less common structure, so it can be more difficult to play back and edit. Many editing programs come with presets to optimize your file for different venues—use them. And sites such as YouTube and Vimeo offer guides for getting the best results, so refer to those before you upload.