WavPack is a completely open audio compression format providing lossless, high-quality lossy, and a unique hybrid compression mode. The compression ratio depends on the source material, but generally is between 30% and 70%. The hybrid mode provides all the advantages of lossless compression with an additional bonus. Instead of creating a single file, this mode creates both a relatively small, high-quality lossy file that can be used all by itself, and a "correction" file that (when combined with the lossy file) provides full lossless restoration. For some users this means never having to choose between lossless and lossy compression.