A tracker1 is a program that is used to make synthetic music. However, 'synthetic' is not really the correct term, since trackers usually perform music by playing a set of digitised instruments at different rates at different times.
How it works
A tracker is made up of several tracks. Each track plays simultaneously and has a certain number of lines, usually a multiple of eight.
By placing a music note every few lines, in any sort of pattern, rhythmic or melodic tunes are stored in a fast and efficient way. In the late 1980s and well into the mid-1990s, there was a massive surge of Tracker based music, made with programs like Protracker, Scream Tracker, OctaMed and Fastracker
These programs were relatively cheap, and when used properly could make very high quality music, much higher than that of a Compact Disc.
How it Began
While it isn't technically correct, it was Protracker on the Amiga which started the tracker craze. There were other programs on the earlier 4bit systems, like the Commodore 64, but they did not have the effect of Protracker.
There were, at the time, hardware constraints, such as only having four hardware channels2, but this was soon fixed by sampling3 the four channels, thus making it only one instrument, which in turn only required one channel.
Soon however, multichannel programs like Octamed, which allowed up to eight channels to be played at once, started to show. Octamed was fairly primitive at this time and technically 'mixed' the eight channels into two.
It was not long after Protracker was released, that programs like FastTracker and Screamtracker came out. All of them could have many more than four channels play instruments at once, but with a loss of quality. By the time FastTracker 2 and ImpulseTracker were released, the quality on Compact Discs was easily replicated, and indeed surpassed.
Where are They Now?
There is still a massive tracking community worldwide, and there will forever be since tracking is a revolutionary way to create music.
A lot of the songs you hear these days (especially remixes, techno, rave, and all of the electronica) will probably have been touched or made by a tracking program.
Octamed is one of the few programs which survived the transition from the Amiga to the PC compatible computers, and is well worth a look for anybody heading into the music industry or anyone who just wants to play around.