This causes lots of confusion because video files aren't quite like the relatively straightforward image file types you get with still imaging. In fact, video files consist of two parts: the 'container', and the audio and video files stored within it. Video is stored using a variety of different 'codecs' – encoder/decoder tools – and one of the most common right now is H.264. But this is not the file, or 'container' format. For example, you can find H.264 video in the MOV and MP4 container formats. The container also houses the audio data, which may itself be in a variety of different formats.
This all sounds a bit of a nightmare, but in practice consumer video devices stick to a relatively small subset of container file/codec combinations and any video editing software worth its salt will be able to open and work with them without any special effort on your part.
