Fuses are components used to protect circuits and are usually made of a metal wire or copper shavings. Their job is to automatically break the circuit when an abnormal current or short circuit occurs, preventing damage to the circuit or electronic device and providing protection. When the current in the circuit exceeds the rated current value of the fuse, it instantly heats up and breaks, preventing damage to the circuit. Choosing fuses with different rated currents and using them with specific electronic components can provide more reliable protection for electronic equipment.