Bumpers are used to get in/out of a commercial break in radio, and are used (are they still a legal requirement in the broadcasting act enforced by Ofcom?) in television as well.
Stings and sweeps in radio are generally also used to bridge two tracks in a two/three in a row back to back sequence.
My user name might look like Hatton Cross, but it's pronounced Throatwobbler Mangrove.