is an internal company-wide system of computer networks
Intranet An intranet is a private network accessible only to an organization's staff.[1][2]A wide range of information and services from an organization's internal IT systems are unavailable to the public, unlike the Internet. A company-wide intranet can constitute an important focal point of internal communication and collaboration, and provide a single starting point to access internal and external resources. In its simplest form, an intranet is established with the technologies for local area networks (LANs) and wide area networks (WANs).[3][4][5]
ARPANET The Advanced Research Projects Agency Network (ARPANET) was an early packet switching network and the first network to implement the protocol suite TCP/IP. Both technologies became the technical foundation of the Internet. The ARPANET was initially funded by the Advanced Research Projects Agency (ARPA) of the United States Department of Defense.[1][2][3][4][5]