A DJ mixer is a device used by disc jockeys to blend and manipulate audio tracks. It allows DJs to control the volume, equalization, and effects of multiple sound sources, such as turntables or digital audio players. The mixer typically features faders, knobs, and buttons that enable smooth transitions between songs and the creation of unique soundscapes. Most DJ mixers also include inputs for microphones and other audio equipment, making them versatile tools for live performances. They can range from simple, two-channel models to complex, multi-channel systems with advanced features. Popular brands include Pioneer, Numark, and Allen & Heath.