MIDI is a relatively new and still developing electronic science 
which has been created for computers and musical instruments. 
Using MIDI, we can...

         1) Synchronize different types of equipment together to 
perform various tasks in unison ...
         2) Record and playback music (MIDI files) ...
 
  First introduced in 1983, MIDI opened the door to communication
between various musical instruments and computers. The General 
MIDI standard was established in 1991 to create a uniform set of 
specifications between different manafacturers. The GM standard
defines things like the minimum # of voices , patch locations,
note numbers for keyboards, etc.
  
  MIDI files are best thought of as recordings of music data.
By music data, I mean that the file contains no sound data, only
MIDI data. The sound comes from the sound card or module when it
recieves MIDI data .A typical MIDI note would contain an on signal,
an off signal, a velocity, a duration, and a channel identifier.
The sound card in turn converts this message to audio. Midi files
come in 2 types, Type 0 and Type 1. Type 0 contains all of the 
MIDI data on one track regardless of channel assignments, and Type 
1 contains the data on separate tracks according to the assigned 
MIDI channels.   

  Most PC computers equipped with a General Midi sound card can 
play back MIDI files with Window's Media Player. Other sound 
cards that are not up to the GM standard (most are not) will play, 
but not well. I recommend the Roland SCC-1 sound card.
 
  Mac users will require a MIDI interface (such as Mark of the 
Unicorn's MIDI Time Piece), sequencing software, and a sound 
module. A sound module is basically an external sound card. Some
sound modules ( such as the Roland Sound Canvas ) eliminate the 
need for an interface by providing a Mac input. I recommend the
Sound Canvas.
 
  For the PC, more refined uses of MIDI (recording, editing, etc.) 
will require the purchase of a MIDI interface and sequencing software. 
Sequencing software is a program which turns your computer into a MIDI 
recording studio. Programs are available for both IBM and MAC. I like 
Passport's Master Tracks Pro for both platforms. Sequencer users will 
also need a MIDI controller keyboard to record data with. 
   
If you have any questions not covered in this text, please
write to me, or visit my MAGIC TRACKS location here on ICNet.