The world of video formats can be pretty confusing, but there are only a few things you really need to know. First, it’s important to note that a video format is more than just its file extension. Extensions like AVI are not, in fact, video codecs—they’re containers. A container is the file format which can use multiple different codecs—such as DivX or x264—to compress a certain standard of video—such as MPEG-4 or H.264, respectively—into a hard-drive friendly amount of space. Here’s what you need to know about both codecs and containers, and what that means for the videos you rip yourself.