An extranet is a private network that uses
the Internet protocol and the public 
telecommunication system to securely 
share part of a business's information
or operations with suppliers, vendors, 
partners, customers, or other businesses.
An extranet can be viewed as part of a
company's intranet that is extended to 
users outside the company. 
It has also been described as a "state of mind"
in which the Internet is perceived as a way to
do business with other companies as well
as to sell products to customers.