An intranet is a private network accessible only to an organization's staff. Often, a wide range of information and services are available on an organization's internal intranet that are unavailable to the public, unlike the Internet. In its simplest form, an intranet is established with the technologies for local area networks (LANs) and wide area networks (WANs). Intranets began to appear in a range of larger organizations from 1994.
An extranet is a controlled private network that allows access to partners, vendors and suppliers or an authorized set of customers – normally to a subset of the information accessible from an organization's intranet. An extranet is similar to a DMZ in that it provides access to needed services for authorized parties, without granting access to an organization's entire network. An extranet is a private network organization. Historically the term was occasionally also used in the sense of two organizations sharing their internal networks over a VPN.
A private computer network that uses the protocols of the Internet.
A private computer network that uses Internet protocols and can be accessed by authorized individuals via the Internet.
a restricted computer network; a private network created using World Wide Web software