Internet, Intranet and Extranet

Internet, intranet, and extranet are three terms that describe "Internet type" applications that are used by an organization, but how do you know if a web application is part of your intranet or part of the Internet?

• INTERNET:

The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide.

• INTRANET:

An intranet is a private computer network that uses Internet Protocol technologies to securely share any part of an organization's information or operational systems within that organization.

• EXTRANET:

An extranet is a private network that uses Internet protocols, network connectivity. An extranet can be viewed as part of a company's intranet that is extended to users outside the company, usually via the Internet.

Internet	Intranet	Extranet
It is a Global system of interconnected computer network.	It is a Private network specific to an organisation.	It is a Private network that uses public network to share information with suppliers and vendors.
Not regulated by any authority.	It is regulated by an organization.	It is regulated by multiple organization.
Thus content in the network is accessible to everyone connected.	Thus content in the network is accessible only to members of organization.	The content in the network is accessible to members of organization & external members with access to network.
It is largest in terms of number of connected devices.	It is small network with minimal number of connected devices.	The number of devices connected is comparable with Intranet.
It is owned by no one.	It is owned by single organization.	It is owned by single/multiple organization.
It is means of sharing information throughout the world.	It is means of sharing sensitive information throughout organization.	It is means of sharing information between members and external members.
Security is dependent of the user of device connected to network.	Security is enforced via a firewall.	Security is enforced via a firewall that separates internet & extranet.
Example: What we are normally using is internet.	Example: TCS using internal network for its business operations.	Example: HP and Intel using network for business related operations.
Users can access Internet anonymously.	Users should have valid username/password to access Intranet.	Users should have valid username/password to access Extranet.
Internet is unregulated and uncensored.	But Intranet is regulated by the organization policies.	Extranet is also regulated by contractual agreements between organizations.