CompuServe launched the first major consumer online service in 1979. Its consumer offering allowed home users to connect by telephone to shared computers and access information, messaging and other services before the modern internet existed.
CompuServe began in Columbus, Ohio, in 1969 as a computer time-sharing business serving corporations. In 1979, it used otherwise idle overnight capacity to offer home access through Radio Shack under the name MicroNET. The consumer service was later marketed more broadly as the CompuServe Information Service, or CIS.
The service grew rapidly after H&R Block acquired CompuServe in 1980. By the mid-1980s, it was one of the largest online services and offered forums, email, software downloads, news and real-time chat. Its CB Simulator, introduced in 1980, became an early mass-market chat system.
The Source began serving the public around the same time, which explains occasional competing “first” claims. CompuServe remains the standard answer for the first major commercial online service aimed at consumers.