The purpose of this tutorial is to teach you how to do a ping. Pinging is a command which tells you if the connection between your computer and a particular domain is working properly.
There are a couple of different ways to get to the Command Prompt screen. In Windows, select the Start button, usually found in the left hand corner, select All Programs, then go to Accessories, and there you will find command prompt. You can also get there by clicking on the start button, and selecting the RUN command from the right hand column. Once selected, type "cmd" (without the quotes) and click OK. Either way will open the Command Prompt box.
Enter the word ping, followed by a space, then the domain name you are checking. Press Enter. The results should show a series of replies, which means the connection is working. The time shows how fast he connection is. However, if you should see a "timed out" error instead of a reply, that means there is a break in the connection somewhere between your computer and the domain. Your next step would be to do a traceroute, and find out where the breakdown is.