People saw the profit that could be gained by controlling their own networks of computers. Thus, before the Internet was open to the general public, there were

People saw the profit that could be gained by controlling their own networks of computers. Thus, before the Internet was open to the general public, there were online services like The Source, Compuserve, GEnie, AOL, which (as far as I can recall) did not interconnect. The Internet is a network of networks, where I can rent a server on a data center owned by A which delivers bits through a pipe owned by B to a customer whose ISP is owned by C, and if I don't like A's terms of service then I can go buy equivalent bandwidth and access from A-prime. That wasn't possible with pre-Internet online providers.