Windows desktop stands two meanings. The first desktop is the one in the windows operating system. After you successfully log into the windows, you will be presented the desktop. Here's what windows xp desktop looks like:

Here is windows 98 desktop:

As you can see the different, on windows xp, the desktop is clean of icons by default. Windows xp's desktop was design to be clean. Users can access all area in the windows from start button at the bottom left of the desktop. See the picture below:

However, users can customize their desktop look such as put in icons and shortcuts as well as changing desktop background. Check out other tutorials in Windows basic tutorials section.

The second desktop refers to the personal computer (pc). Back to the early days, computer comes in many different shape such as tower, mini tower and desktop. The one called the desktop is a computer which can be put on the table with a monitor on it. Here is a sample picture:

Nowadays all personal computers, tower or mini tower, all called desktop.