Kevin325i ... howstuffworks is an awesome site ... thanks.
And to the other guy who initially asked the question. If you wanna learn more about repairing your car or performing maitenance goto amazon.com and type in "haynes bmw" you should get a list of manuals and choose the one that corresponds with your car. Their great.
98' BMW 328i - Jet Black, Black Leather, Alpine CDA-9831 HU
<span style='color:red'>For Sale:</span> Sony CDX-F5000 Xplod w/ Wiring Harness, iBook G3 900 Mhz 640 MB SDRAM w/ Original Box and Software + OS X Panther + Microsoft Office
(PM on any offers, Going on E-Bay soon ...)