An audio compressor is a device used in music production and sound engineering to control the dynamic range of audio signals. It reduces the volume of loud sounds and boosts quieter ones, making the overall sound more balanced. This helps prevent distortion and ensures that all elements of a mix can be heard clearly. Compressors can be found in both hardware and software forms, often used in recording studios and live sound settings. They are essential tools for achieving professional-quality audio, allowing for greater consistency in volume levels across different tracks and performances.