What is Matroska?
(Note: simply copied from www.matroska.org.) Matroska aims to become THE Standard of Multimedia Container Formats. It was derived from a project called MCF, but differentiates from it significantly because it is based on EBML (Extensible Binary Meta Language), a binary derivative of XML. EBML enables the Matroska Development Team to gain significant advantages in terms of future format extensibility, without breaking file support in old parsers. If you need any more info please head over to Matroska’s homepage.