Mechanical licensing is the licensing of musical compositions for use on CDs, Spotify, iTunes, and other physical or digital configurations. This is required under U.S. Copyright Law, regardless of whether or not you are selling the copies that you made.
Whether the use is professional, semi-professional, amateur, or educational, and whatever the eventual purpose of the film (including posting on YouTube) a synchronization license for the use of the music is required. This is also called synchronization rights or synch rights.
All theatrical presentations (e.g. choreography, dance, stage action, plays) require permission and a dramatic license (also calledgrand rights)covering royalties payable and any score materials required.