Final answer:
Paul Baran contributed to the development of packet-switching networks, a fundamental technology for the Internet, but he did not develop TCP/IP protocol, the World Wide Web, or Ethernet technology.
Step-by-step explanation:
Paul Baran is widely credited for his pioneering work on packet-switching networks, which is a foundational technology that made the Internet possible. In the 1960s, as part of the efforts to create robust, fault-tolerant communication systems, Baran developed the concept of a network that could efficiently route data using packets. This innovation was distinct from the earlier circuit-switching methods where a dedicated circuit was required for the duration of a communication session. The ideas of packet-switching were later implemented in the ARPANET, giving rise to the network of networks we now know as the Internet.
Baran's contribution does not include the TCP/IP protocol, which was developed by Vinton Cerf and Robert Kahn in the 1970s, nor did he have a hand in creating the World Wide Web, which was invented by Tim Berners-Lee in 1989. Additionally, Ethernet technology, which is a local area network (LAN) technology, was developed by Robert Metcalfe and others at Xerox PARC.