RF64
The EBU's extension of WAV with 64-bit size fields, so a recording no longer stops dead at 4 GB.
WAV inherited 32-bit length fields from RIFF, which was generous in 1991 and stingy the moment someone recorded twelve channels at 96 kHz through an entire concert. RF64, published by the European Broadcasting Union as Tech 3306, makes a minimal change: the first four bytes become RF64 instead of RIFF, the old size fields are set to 0xFFFFFFFF, and a new ds64 chunk carries the real 64-bit lengths. Everything else, Broadcast Wave metadata included, looks as it always did.
A neat trick means the recorder never has to know in advance how long the take will be. It starts writing an ordinary WAV with an empty JUNK chunk as a placeholder and rewrites it as ds64 if the file crosses 4 GB. The ITU's BW64, which carries object-based audio for formats like Dolby Atmos, builds directly on RF64.