Intranet
An intranet is the internal computer network of a company or organization. This network ensures that all computers within the organization are connected to each other - and usually to the Internet.
Intranet can also mean an internal company website. This site is only accessible to employees and contains information that is only for the company itself. Think announcements, a calendar, a facebook, and general protocols and forms.
The information visible to a user in the extranet can often be tailored to their department and position within the organization. Intranet environments can also be used to facilitate the flow of information within projects.
