What are Switches and Fuses?
As mentioned earlier, short circuits can be damaging to the voltage source. One way we have developed to protect equipment is to use fuses in case of an accidental short circuit. The fuse is meant to melt and break, stopping the current from flowing with an open circuit if more than the rated current tries to flow through it.
Switches are easy way of letting current flow in a circuit when the switch is closed, and allowing no current to flow through when the switch is open.