M4B is an audio filename extension for AAC format, which is developed by Apple Inc. It is mainly used on podcast and audiobook files. Typically, M4B files contain audio and other metadata like images, hyperlinks, and chapter markers. M4B files are DRM copy-protected and can be opened on Apple iTunes and QuickTime Player.
DivX is a video codec brand developed by DivX, LLC. This video codec is mainly compatible with Windows programs, although it can also be embedded on game consoles, alar clocks, car stereo, and more. Today, there are three primary DivX codecs, including MPEG-4 Part 2, HEVC Ultra HD, and H.264/MPEG-4 AVC DivX Plus High Definition video codec.
DVD/Blu-ray Players Alarm Clocks Car Stereo X-Box 360