Chimes are sets of 22 or fewer bells placed so as to broadcast sounds over a wide area, usually for the purpose of telling the time, summoning people to religious services, marking events or alarms, or playing music. This is a common usage for bell towers. Sets of 23 or more bells are generally classified as carillons, which have a greater musical range than chimes.

The bells are arranged to make sounds audible beyond their immediate support. The purpose can be signaling or music, without requiring both.

A carillon has at least 23 bells. The number of bells distinguishes the two instruments; both can be housed in a bell tower.