The heating effect of current refers to the phenomenon where an electric current passing through a conductor generates heat. This occurs due to the resistance of the conductor which causes the electrons to collide with the atoms of the material and transfer their kinetic energy to them thereby increasing the temperature of the conductor. The amount of heat generated is proportional to the square of the current and the resistance of the conductor as described by Joule's law (P = I² × R). This effect is commonly observed in electrical appliances such as toasters, electric heaters and lightbulbs where the current passing through the heating element causes it to heat up and produce heat. It can also occur in electrical wiring and other components leading to potential fire hazards if the current is too high or the wiring is damaged.