Answer: The World

Throughout the 1980s, there were many thriving online service providers. Early adopters of the personal computer, armed with a modem and an open phone line, could call into online services like CompuServe where they would find discussion boards, file sharing, and more.

The keyword here, however, is online. While these early providers had thriving internal networks they were not, in fact, connected to the greater Internet. At the height of their popularity, the Internet was still reserved for research and military use, well outside the reach of home users. That changed in 1989 when a small software company, Software Tool & Die, launched The World: the first commercial Internet service provider.

While Internet access is so commonplace today as to be considered almost like a utility akin to electricity and water service, The World was highly controversial at the time of launch. Government institutions and universities blocked, threatened to block, or even attempted to shut down The World on the grounds that the Internet was not for commercial use and should be reserved, as it had been, for science and military development. The National Science Foundation stepped in on behalf of Software Tool & Die and granted them permission to provide public Internet access on an experimental basis.

Although it would be easy to assume that The World is long gone and now just a footnote in the evolution of the Internet, the service provider still exists and as of 2012 had 1,750 active users still dialing in.