A jack plug is a type of electrical connector commonly used to connect audio devices, such as headphones and speakers, to a sound source. It typically features a cylindrical metal tip that fits into a corresponding socket, allowing for the transmission of audio signals. Jack plugs come in various sizes, with the 3.5mm and 6.35mm (1/4 inch) being the most common. These connectors are often found in consumer electronics, including smartphones, laptops, and musical instruments. The design of a jack plug allows for easy insertion and removal, making it a popular choice for portable devices.