Electronic keyboards include synthesizers notably the Moog synthesizer), samplers and frequency divider organs. With the use of sampled sounds and MIDI, true synthesizers have become rare, and more and more the general term electronic keyboard is being used.
Compare to electric instruments such as the Fender Rhodes piano, and true electric pianos such as the Yamaha electric grand. On the borderline between the two categories are the Mellotron and the traditional Hammond organ.