The MIDI port is a different flavor of the serial port developed to connect musical devices to your PC. The most common type of musical device is the electronic keyboard. Note that most sound cards let the game port double as a MIDI port.

The USB or Universal Serial Bus is the second generation of the serial port. The data transfer rate of this port is much higher than the older serial port. You can connect up to 128 peripheral devices to each individual port in a daisy chain.