Play, Create, Learn... it's all MIDI ... it's in musical instruments, computers, cell phones, and many other products from well known companies like Microsoft, Apple, Nokia, Sony, Yamaha, & hundreds more consumer products companies. Most popular recorded music is written and performed using MIDI-equipped electronic keyboards (aka "synthesizers"). Much music is also written on computers using "Sequencers" and/or "Digital Audio workstations".
How to write a song in 10 steps as a beginner? The infographic shows you how to get song ideas, write lyrics, find chords, structure the song and record online for free. Sample great original musical pieces at http://cdbaby.com/Artist/RogerLehman