Material eXchange Format (Mxf)
"The Material eXchange Format (MXF) is an open file format targeted at the interchange of audio-visual material with associated data and metadata. It has been designed and implemented with the aim of improving file-based interoperability between servers, workstations and other content creation devices.". - Pro-MEG
Mxf is a media "wrapper", a specification for providing interoperability of media playback. It is closely associated with Advanced Authoring Format (AAF) - they share a similar object design. They can be used together, Aaf holding complex composition data and Mxf containing media, or independently.
Mxf design was initiated by the Pro-MPEG Forum, and has now been standardized by SMPTE.
Recent SMPTE Mxf standards include:
SMPTE 377M-2004: Television - Material Exchange Format (MXF) File Format Specification
SMPTE 378M-2004: Material Exchange Format (MXF) — Operational pattern 1A (Single Item, Single Package
SMPTE 379M-2004: for Television - Material Exchange Format (MXF) - MXF Generic Container
Bruce Devlin has written a good overview of MXF