How True is This?
"The most future-proof audio-video container formats today are QuickTime and Matroska. The ISO/IEC 14496-12:2004 (MPEG-4 Part 12: ISO base media file format) is the basis of MP4, M4V, and M4A files and it's a stripped-down version of Quicktime. Matroska is an independent and completely free and open-source community developer container format that implements most of the features of the QuickTime container format. In practice, Matroska containers have more varied content encodings since the user base uses a much wider range of tools to create the files. The ISO container is the most widely supported in commercial products. There's also Microsoft's Advanced Systems Format (ASF) which is proprietary to them and the basis for WMV and WMA files which is also fairly flexible." -- James McInnes