In electronics and electrical engineering, a fuse (from the French fusée, Italian fuso, "spindle") is a type of low resistance resistor that acts as a sacrificial device to provide overcurrent protection, of either the load or source circuit. Its essential component is a metal wire or strip that melts when too much current flows through it, interrupting the circuit that it connects.  Short circuits, overloading, mismatched loads, or device failure are the prime reasons for excessive current. Fuses can be alternative to circuit breakers.