Is a media data format created by Apple. Named 'Quicktime' and is opened by a program with the same name. This format contains several tracks, each of which can store audio, video or text. Supported by a large number of encodings and in a single file, each element can use its own codec.
Xvid (formerly 'XviD') is a video codec library following the MPEG-4 video coding standard, specifically MPEG-4 Part 2 Advanced Simple Profile (ASP). It uses ASP features such as b-frames, global and quarter pixel motion compensation, lumi masking, trellis quantization, and H.263, MPEG and custom quantization matrices.