Some think of the relationship between libraries and the Internet as a competition, and a fairly recent one at that, with search engines like Google replacing libraries. In reality, libraries have had a close relationship with the Internet that dates back nearly 50 years, long before the existence of Google or the web. This entry describes the longtime relationship between libraries and the Internet and discusses library materials available online, the Internet as a tool to provide service to patrons, institutional repositories, and ways of improving discoverability.