What is a MIDI input/output?
No. MIDI is a form of “networking” music devices to keep them synchronized. You can do some neat stuff like use a MIDI keyboard to control stage lights. Or use a MIDI vilion to control a MIDI keyboard. It is a simple but effective protocol that has fields saying what note you played, for how long, etc. The ports in the back are sort of like network cables. IN is for things connecting to you as a slave. And out is for connect your device as a slave to another host. (I might have this wrong). There is also now USB midi which makes this remarkably easy to connect a “software instrument” on your computer to play alongside with your physical instrument. The key to remember is MIDI is a protocol, a language for devices to communicate with each other. Just like computers have the “Internet Protocol” to talk to other computers, MIDI was designed for simple communication between musical devices.