The original PCs had notoriously bad sound capabilities. PC game makers forced a sound solution in the form of a niche industry - PC sound cards. Sound cards have proven handy even today. By attaching a quality sound card, you can replace the rudimentary internal 'sound card' in today's standard PC, with electronics capable of supporting really decent audio.
There are basically two types - the FM Synthesizer and the wave table lookup. In the FM Synthesizer, the chip understands the characteristics of various sounds, and creates these on the fly, so to speak. The wave table lookup, on the other hand, actually stores recorded samples of the sounds in the hard drive or card buffer, and works by assembling these sounds into the correct arrangements. The wave table lookup types tend to be pricier than the FM synthesizer, but the sound quality is normally richer and with deeper harmonics.
Then came the Web. Internet users quickly became eager to have electronic access to the latest music from their favorite groups. Enter MP3. In digitized sound, a low end speaker can sound acceptable. But digitized sound files are so HUGE that it's downright impractical to try to store or send more than a few minutes worth of audio. MP3, or MPEG (ISO's Moving Picture Expert Group) audio Layer 3, is a fancy compressed version of the standard wave file. It makes it practical to take a super high resolution CD-ROM, make a lower resolution digital copy of its sounds, and then compress the resulting file in a roughly 10 to 1 ratio, to arrive at an .mp3 file. MP3's intent is to deliver the quality of the original record, which MIDI will not. MIDI's intent, on the other hand, is a tool to compose music and drive music synthesizers.
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