The complex web of servers consists of computer systems installed with Web-server software and connected to the Internet. These servers can be found in any facility with Internet connectivity. The process of maintaining and operating one of these servers is called Web hosting. Web hosting can be conducted in-house by the owner of the Web site, or it can be outsourced to a Web presence provider (WPP).

WPPs are typically companies with one or more data-center facilities that are connected to the Internet. Web hosting provided by WPPs can vary widely with respect to service quality and cost. Some providers consist simply of a room in the basement of a house and a tier-1 (T1) line connected to the local ISP. Others, however, are corporations with state-of-the-art hosting centers consisting of redundant fiber paths for high-speed Internet connections, redundant electrical power sources, a dry pipe–fire suppression system, and an experienced operations group, available 24 hours a day, seven days a week.

Web hosting can be provided on a shared computer environment or on a dedicated computer system. When a Web site consists only of standard HTML code and receives a small number of visitors, shared hosting service is the best solution. When a Web site consists of complex common gateway interface (CGI) scripts and proprietary programs and receives a large number of visitors, dedicated hosting service is the best solution.