A USB audio interface is a device that connects musical instruments, microphones, or other audio sources to a computer. It converts analog audio signals into digital data, allowing for high-quality recording and playback. These interfaces often include features like preamps, headphone outputs, and MIDI connectivity, making them essential for home studios and professional setups. Using a USB audio interface improves sound quality compared to a computer's built-in sound card. They are compatible with various software applications, enabling musicians and producers to create, edit, and mix audio efficiently. Many models are portable, making them convenient for on-the-go recording.