A thermocouple is a device used to measure temperature. It consists of two different types of metal wires joined at one end, creating a junction. When this junction is heated or cooled, it produces a small voltage that can be measured and converted into a temperature reading. Thermocouples are widely used in various applications, including industrial processes and household appliances. These devices are popular because they are durable, inexpensive, and can measure a wide range of temperatures. They are often found in equipment like ovens, furnaces, and thermometers. Different types of thermocouples are available, each suited for specific temperature ranges and environments.