Fuse

[huseyin61]

What is Fuse?

[Jay70]

Fuse means to unite or blend. 

 Unless you mean what is an electrical fuse?

 In which case it's a device which is placed in an electrical circuit which is designed to break the continuity of the circuit if a fault occurs.  The fuse is rated at just above the normal operating current consumption of the circuit.  If a fault occurs and a higher than normal current is passed through the fuse which excceds the fuses current rating and  the wire inside the fuse will melt.  Ths will result in the applied voltage source being disconnected from the faulty circuit.  They are fitted for safety reasons as if the supply wasn't broken the faulty circuit could cause a fire.

[BRFCC]

Are you stupid?