Public domain music is music that can be used and shared by anyone, without needing to pay or get permission from the original artist. It is music that is no longer owned or controlled by anyone, so it is free to be used by anyone. It could be an old song that has been around for many years or something a musician has decided to give away to the public. To use public domain music you do not need to pay the artist or have permission from them because no one owns it.