What are MIDIs and how do I use them..?
 

I don't know how to use MIDIs but I downloaded "bwmidi" which was "potentially dangerous" and it's excellent in sound and quality... however, I don't know how to use it... how DO I use this set?

Midis are just a set of instrument instructions and as such will sound different on different hardware and software depending on how they interpret the instructions. iTunes is able to convert midis to mp3s, which you can then put on your music playing device or use for other projects.

I see! that is cool.

Don't forget to give credit to the people who make the MIDIs that you use. A lot of people would want credit where credit is due.