Which is better quality WAV or MP3?

The .WAV format offers completely uncompressed audio. The audio is not reduced in quality, or changed in any way. However, the file size is very large. .MP3, on the other hand, compresses the audio to achieve smaller file sizes. The files can be up to ten times smaller than its .WAV counterpart, but the audio will be reduced in quality. Most people do not notice this difference, or care about it, but most audiophiles, or people with high-end audio equipment agree that .WAV is preferable.

It's all about priority. What do you want more, better quality, or smaller file size?

.WAV = High quality, big files.

.MP3 = Lower quality, smaller files.