A MIDI controller is a hardware or software that generates and transmits Musical Instrument Digital Interface (MIDI) data to another MIDI device, typically to trigger sounds or control parameters of an electronic device. They are multiple MIDI devices such as control surfaces, pads and drums controller but the most commonly used controller is the MIDI keyboard. Brands like Akai, Alesis, M-Audio, Novation and Native-Instruments have great variety of MIDI controller available.