Sometimes artists will release (or have leaked) early rough demonstration recordings, often appearing as B-sides or bonus tracks on deluxe albums. These are normally recorded live and immediately committed to disc, tape or mp3 (or other) with little-to-no added production or further mixing. Artists will usually record demos with the intention of sending them off to a publisher, producer or guest artist to give them a taste of their sound.

Demos are generally distinguishable from their commercially released versions by the noticeable difference in sound quality, as demos tend to be recorded using cheaper equipment, such as an 8-track tape recorder, often at home, or at least not in a professional studio. They also may have differences in lyrics, melody, chord progression or instrumentation.

Songs:

• “My Best Dress” (demo) by Florence and the Machine
• “Temptation Two” by The Cure
• “While My Guitar Gently Weeps” (Esher Demo) by The Beatles