Cooling can be used allthrough out the computer itself. But I will focus on case cooling and what can be used to cool the case and insides.

Case cooling is used to make sure that the parts inside do not overheat causeing the system to fail and soon there after replacement of the parts that happened to fail due to heat. Heat is the major enemy of computers and its components.With out a good cooling system for your computer you might run into some problems depending on what you are planning to use it for.

The cooling system for the case works by bringing in more air to the case and pushing out the hot air that had previously been circulated thoughout the case to cool the components off.

For this example I will be using a water cooling kit. The kit http://www.xoxide.com/zalman-reserator-1-v2.html is made in Korea. Zalaman is a aftermarket computer parts manufactuer from korea and they are more highend parts.

The computer cooling came around in the 60's with the invention of the computer. There were heat problems from the very start and the first thing used were transistors then gradually moved into fans and liquid cooling.

Computer cooling is controlled by temp sensors on the mobo that detect the heat and adjust the fan speed accordingly to keep the system cool.

One probelem is that dust gets caught in the fans and clogs them up and can cause failure. One advantage of having a watercooled system is that there is less chance of the dust getting into the fans and clogging them up. This is acheived because there are no fans to speak of it uses supercooled water or some other material to cool the case.

There are programs that can moniter the temp of the computer and the speed of the fans such as speed fan[http://www.almico.com/speedfan.php], or everest for vista[http://www.lavalys.com/], or http://www.hmonitor.net/. There are many others but these are a few. One easy to keep heat down is to dust your case or use a Co2 duster to remove the dust off of all of the case.

There are many liquid cooling conventional cooling ways. such as This system is a fanless watercooling system. http://ryanpbarc.pbwiki.com/f/xoxide_1966_20327273.gif Things that are needed would be a tank for the coolant, a water block,and some coolant. These systems should not be installed unless you know what you are doing. The cooling can consist of high quality anti-corrosion agents for various materials including copper, aluminum, and plastic, that prevents corrosion for long term operation.

When choosing a cooling system you need to evaluate your needs and then decide what type of system to purchase. The most common is air cooling which is for more home a personal use. If you are going to be using the computer for professional applications,gaming or rendering. You would want to go with a water cooled system.