...The most convenient is to use the concept of libraries that handle the big market music players: iTunes, Amarok, Windows Media Player, Google Music, ..etc
The labels of music files contains all information on artist, album, genre, title, lyrics ... etc, associated with a song. This information is used by music players to manage their libraries. A good labeling enhances the user experience.
Do you want your music in the cloud? Then before, you have to check the tag information is correct before incorporating. If you do not, you will be unable to locate many of your songs.