The Joule effect, also known as Joule heating, refers to the process where electrical energy is converted into heat when an electric current passes through a conductor. This phenomenon occurs due to the resistance of the material, which causes energy to be dissipated as heat. The effect is named after the physicist James Prescott Joule, who studied the relationship between electricity and heat in the 19th century. In practical applications, the Joule effect is utilized in various devices, such as electric heaters and toasters, where heat generation is desired. However, it can also lead to energy losses in electrical systems, making it important to manage heat dissipation in components like resistors and wires to ensure efficiency and prevent overheating.