None, FLAC is
*.flac
Wav is more or less “raw” audio. It is typically not compressed.
Ogg Vorbis is a lossy compressed format. It reduces the “quality” of the audio in exchange for a smaller file. More often than not, the change in quality is not perceptible to the human ear.
Other lossy compressed formats include MP3, AAC, and Ogg Opus. There’s plenty of neuance to compare between these lossy formats. But if you don’t already know about them, just assume Ogg Opus is best, Ogg Vorbis and AAC are the same, and MP3 is worse. AFAIK Spotify uses Ogg Vorbis, but they may have upgraded to Ogg Opus by now.
FLAC is a losslessly compressed format. It compresses the raw audio without changing the quality at all. All lossless formats are the same quality as Wav. The only differences between the lossless formats are the size of the file and the CPU cost to decompress the data.
Have more questions about codecs? Just ask! I’m not an expert but I do know a decent bit about this stuff.
.wav files store volume levels (typically, but often higher) as a 16bit value 44100 times a second (again, typically, but often higher). This allows frequencies up to 22050Hz to be stored without losses. A lot of this is useless information, because most people don’t hear anything above 16kHz, which only gets worse with age. Other parts of this might be useless information because of complex low frequency interaction with the inner ear which occlude some higher frequencies (psychoacoustics was a long time ago, can’t explain it in detail). .ogg and .mp3 filetypes, among others, use that to simply cut frequencies that (probably) aren’t heard. This process saves a lot of data, but results in lower resolution, especially in the higher frequencies (look up comparisons for 128kBit/s vs 320kBit/s MP3, you’ll hear the difference immediately on pretty much anything other than phone speakers.)
If file size is an issue, .ogg is great, if quality is the most important, go for .flac, as flac files also don’t loose any quality while having file sizes between the two, though compatibility might be a problem on older systems.
Depends on what counts as “better”.
Better quality? WAV, since it’s lossless.
Better efficiency? OGG (well, Vorbis) since it compresses pretty well, but you’ll still get a (minor) loss in quality.
That said, both of those formats are old news and should only be used if you have weird, specific compatibility needs. For lossy compression, OGG/Vorbis has been succeeded by Opus; it’s what YouTube uses, compresses fantastically, and is supported by damn near everything. For lossless, FLAC (Free Lossless Audio Codec) is still the gold standard: you can reduce file sizes by as much as 60% with literally zero loss in quality. If you can, use one of those.
