Time switch is a device that controls the automatic on and off of electrical appliances and lighting systems. It provides the ability to program the device to turn on or off at specific times of the day, week or month, providing convenience and energy efficiency. Synonyms for time switch include timer, clock switch, programmable switch or timer switch. Timer is a commonly used synonym for time switch, as it implies a device that counts down or up to a specific time before switching on or off. Programmable switch or timer switch are also synonymous with time switch since they offer the ability to program different schedules based on specific requirements.