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.
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.