The internet was not invented as much as it evolved from a simple message and filing sharing mechanism to an advanced worldwide network of computers. The internet can trace its roots to the Department of Defense Advanced Research Projects Agency's (ARPA) use of a "galactic network" of computers connected via telephone lines. ARPAnet was designed to defeat a Soviet attack on the communications infrastructure in the early 1960s. However, technology wasn't up to the task. In 1969, the first "login" crashed the network. By the end of 1969, only four computers were hooked onto APRAnet. During the early 1970s more computers were added as the complex nature of computer communications was better understood.
Vinton Cerf, a computer scientist, may be considered the grandfather of the modern internet. He developed the Transmission Control Protocol (TCP) and the Internet Protocol (IP). These two functions allowed different and unknown computers to network. It was this procedure that made the worldwide web possible. January 1, 1983, is considered the official birthday of the internet because of Cerf's developments in connecting non-networked computers.
Using Cerf's protocols, scientists and the military used the internet to trade information and data files directly. In 1991, Tim Berners-Lee gave birth to the World Wide Web (WWW), a network of information anyone could retrieve. Since that time, developers have constantly sought ways to engineer software to make browsing the internet better. Mosaic, later named Netscape, was the first user-friendly application with links and pictures. In 1992, Congress allowed the internet to be used for commercial purposes, flooding the internet with business webpages.