The internet as we know it today is the result of the work of many individuals and organizations over several decades. However, the concept of a global network of interconnected computers can be traced back to the 1960s and the work of Paul Baran and Leonard Kleinrock.
Baran, who worked for the defense contractor RAND Corporation, developed a proposal for a distributed communication network that could withstand a nuclear attack. His work laid the foundation for the development of packet-switched networks, which are the basis for modern computer networks.
Kleinrock, a professor at UCLA, developed the theory of packet-switching and wrote one of the first books on the subject. He also played a key role in the development of the first wide-area computer network, the ARPANET, which was funded by the U.S. Department of Defense.
Other important figures in the development of the internet include Vint Cerf and Bob Kahn, who developed the TCP/IP protocol that is used to transmit data over the internet, and Tim Berners-Lee, who invented the World Wide Web and the first web browser.