Bumper music, or a bump, is a term used in the radio broadcasting industry to refer to short clips of  signature or theme music used to buffer transitions between programming elements.  Bumper music is commonly employed when a syndicated program takes a break for local station identification or "goes to a radio commercial." More often than not called a "Bump" in today's radio; NPR also uses the term "Button". It is also referred to as "rejoiner music" when the bumper music marks the end of a local break on a radio network.