Web browsers such as Microsoft Edge, Firefox, Chrome, and Safari are among the most popular network applications in the world. People use these browsers for basic information and other needs, including online shopping and casual gaming. Web server communication relies on network protocols.

Web browsers and web servers function together as a client-server system. In computer networks, client-server is a standard method of designing applications in which data is stored in central locations (server computers) and efficiently shared with any number of other computers (clients) on request. All web browsers function as clients that request information from websites (servers).

Numerous web browser clients can request data from the same website. Requests can occur at different times or simultaneously. Client-server systems conceptually require that all requests to the same site be handled by a single server. In practice, however, web servers are often built as a distributed pool of server computers, because the volume of requests to web servers can sometimes become very large.

For websites that are popular in different countries around the world, this web server pool is geographically distributed to improve response time for browsers. If the server is located closer to the requesting device, the time it takes to deliver the content is faster than if the server were further away.