Wikipedia
iXML is an open standard for the inclusion of location sound metadata in Broadcast Wave audio files. This includes things like Scene, Take and Notes information.
It is the result of extended discussions between the various manufacturers of Field recorders, and editing systems. It is designed to standardise the exchange of metadata between these systems.
The iXML specification describes an WAV RIFF chunk in BWF files which contains standard XML data following the iXML specification.
Prior to the development of the iXML specification, the film and TV industry relied on the BWF bext description chunk which was used differently by many vendors to roughly encode some small metadata, but was invariably undefined, with too little space for full information. Whilst many systems tried to read what they could from the bext data, because of no specification and limited space, bext usefulness was limited.