Good intro read
https://reverb.com/news/midi-basics-...dern-producers

MIDI is not the end of analog music-making. It's not overly complicated. It's simply another tool you can use alongside your trusty Telecaster or vintage Moog.
MIDI (Musical Instrument Digital Interface) is the digital control language that gives electronic instruments the ability to communicate with each other. You can look at MIDI data as digital sheet music that dictates messages written with your DAW to plugins loaded on your track. By utilizing MIDI in your musical workflow, you can control almost every element of your sound while playing on stage and recording in the studio.
Check out our guide below for an introduction to some basic MIDI capabilities, like creating new MIDI note events in your DAW and shaping sounds with external MIDI controllers.

https://reverb.com/news/midi-basics-...dern-producers