WavPack is an open lossless audio codec notable for its flexible hybrid mode. In pure lossless mode it works like FLAC or ALAC, shrinking a WAV while restoring it bit-for-bit. In hybrid mode it splits the file into a relatively small lossy 'core' that is playable on its own, plus a 'correction' file that, when present, upgrades the core back to fully lossless. That lets you keep a compact everyday version and an exact archive from the same encode. WavPack also handles high bit depths, many channels, and even DSD, which keeps it useful in archival and audiophile niches, though FLAC's broader support makes it the more common lossless choice.
