PPL collects and distributes money for the use of recorded music on behalf of record companies and performers.
PRS for Music and the Mechanical Copyright Protection Society (MCPS) collect and distribute money for the use of music and lyrics on behalf of songwriters, composers and publishers.
Even if you are registered with PRS for Music as a songwriter or composer, you may also wish to register with PPL to make sure that you receive any recorded music licensing income you are due as a performer or recording rightsholder as well.
Find out more about the difference between PPL and PRS for Music here.