What are the different ways to connect external devices to a computer for music production, and how do USB MIDI ports play a role in this connectivity?

External devices can be connected to a computer for music production through various methods such as USB, MIDI, and audio interfaces. USB MIDI ports are specifically designed to connect MIDI devices like keyboards, controllers, and synthesizers to a computer for sending and receiving musical data. They play a crucial role in enabling communication between these external devices and music production software on the computer.