Some Existing Houses still have fuses instead of Circuit Breakers located in the switch box.
Fuses can be quite annoying if the fuse wire blows and there is no spare fuse wire handy.
To avoid this type of issue from affecting you, the fuses can be replaced with Circuit Breakers, allowing easy resetting in case of a tripped Circuit breaker
Circuit Breakers provide short circuit and over current protection such as when a power circuit has been overloaded.
Circuit breakers do not act as a Safety Switch for personal protection against electrocution; a Safety Switch needs to be installed for protection against electrocution.