MIDI Interface refers to the ability of a DJ controller to communicate with other musical devices using a standardized language called MIDI. It is not about the transmission of sound, but about digital commands and data, such as "play this note" or "change tempo." Every DJ controller communicates with computer software precisely via MIDI, usually through a USB cable. However, if this parameter is explicitly listed for a controller, it means it is also equipped with classic five-pin "MIDI IN" and "MIDI OUT" connectors. The "MIDI OUT" port allows sending data from the controller to external devices, such as synthesizers, samplers, or drum machines, and controlling them directly from it. Conversely, the "MIDI IN" port is used to receive MIDI signals, allowing the controller's functions to be controlled from other external hardware. This makes it possible to integrate the DJ controller into a wider musical system and synchronize it with other equipment.