An audio interface is a device that connects musical instruments, microphones, and other audio equipment to a computer. It converts analog signals, like sound from a microphone, into digital data that your computer can understand. This allows musicians and producers to record high-quality audio and play it back through speakers or headphones. Many audio interfaces also come with built-in preamps, which boost the signal from microphones, and various inputs and outputs for connecting different devices. Popular brands like Focusrite and PreSonus offer models that cater to beginners and professionals alike, making it easier to create music at home.