Station idents (also called 'sounders' or 'stingers') are intervals between broadcast periods, shows and similar in both radio and television that identify the station. Station idents are often based around a central channel theme to help promote and build the channel. In US FCC law all radio and television channels are required to ident. The idea is that due to the overwhelming number of channels on both television and radio a listener should be able to tell which broadcaster he/she is listening to. It used to be that FCC demanded all channels to ident every hour within a 3 minute window. Law's have since relaxed to some degree, but many stations in the US still abide by this practice. More recently idents have become ever increasingly prevalent as a means to advertise future broadcasts on the station by means of combining channel ident with feature ident.