Web servers are computers on the internet that host websites, serving pages to viewers upon request. This service is referred to as web hosting.

Every web server has a unique address so that other computers connected to the internet know where to find it on the vast network. The IP (Internet Protocol) address looks something like this: 69.93.141.146. This address maps to a more human friendly address, such as wiseGEEK.

Web hosts rent out space on their web servers to people or businesses to set up their own websites. The web server allocates a unique website address to each website it hosts.

When you connect to the internet, your personal computer also receives a unique IP address assigned by your ISP (internet service provider). This address identifies your computer's location on the network. When you click on a link to visit a website, like www.wisegeek.com, your browser sends out a request to wiseGEEK's IP address. This request includes return information and functions like a postal letter sent across town, but in this case the information is transferred across a network. The communiqué passes through several computers on the way to wiseGEEK, each routing it closer to its ultimate destination.

When your request reaches its destination, the web server that hosts wiseGEEK's website sends the page in HTML code to your IP address. This return communiqué travels back through the network. Your computer receives the code and your browser interprets the HTML code then displays the page for you in graphic form.

The more powerful the server, the faster it can serve up website pages. Slower, smaller servers may result in frustrating lag time for viewers. High traffic can also slow servers that are not powerful enough to handle high volumes of data exchange. This lag time should be a concern if you are shopping for a web host. Most web hosts have a page dedicated to sharing technical information about their web server, including speed, capacity, network configuration and other details.

In theory, web servers stay connected to the Internet 24/7, 365 days a year. In truth they experience occasional downtime due to maintenance and technical problems. Web servers with consistent records of an uptime of 99.5% or better are considered reliable.