An external sound card is a device that connects to a computer or other audio equipment to enhance sound quality. Unlike built-in sound cards, which are integrated into the motherboard, external sound cards can provide better audio performance, support for multiple audio channels, and various connectivity options. They are often used by musicians, gamers, and audio professionals to improve their listening and recording experiences. These devices typically connect via USB or other ports, making them portable and easy to use. Many external sound cards come with features like headphone amplifiers, MIDI support, and customizable audio settings, allowing users to tailor their sound experience to their preferences.