A turntable is a modern phonograph, also known as a record player or record machine. They are a popular machine commonly used by Disc Jockeys. Turntables are distinguished from older phonographs by the fact that they have electrical pickups instead of a purely mechanical one.
Note: If a phonograph is basically flat and has a mobile arm, it's probably a turntable. If it has a cone, or a tube-style fixed arm, it isn't.