Fuse boxes (FBs: Fuse boxes) or circuit breaker boxes (CBBs: Circut breaker boxes) contain fuses that stop an electrical circuit from overloading. An overload can be dangerous in several different ways, so a fuse box is an important safety feature. (Many newer homes use circuit breakers instead.) When a fuse "overloads", it "blows" and that circuit will stop working until it is fixed, usually by replacing the fuse. It may also be necessary to do something to stop the overload from occurring again.