TL;DR: Intranets are usually employee only. Extranets are accessible to employees and trusted outsiders. Anyone with an Internet connection can access the Internet.
Intranet – Private
Extranet – Semi-private
Internet – Public
What is an Intranet?
An intranet is a private network, typically accessible via the Internet and restricted to certain users – like employees of a company.
What is an Extranet?
An extranet is a private network, typically accessible via the Internet and restricted to users within a certain company and their vendors or trusted partners.
What’s the difference between an Intranet and an Extranet?
An intranet is private from the prying eyes of the outside world and may include company information that should only be seen by trusted users (such as employees).
An extranet is also private from the public but may include information the company is willing to make visible to others and require approved access to view.
A Quick Example of the Differences
For example, a manufacturing company may have an intranet that their employees use to communicate with other employees, learn about company announcements, view customer data, and share documents.
The same manufacturing company may have an extranet where their approved wholesalers can go to
The manufacturing company may also have a site on the Internet where the general public can learn more about the company, what they manufacture, and how they can become an approved wholesaler.
How do extranets and intranets differ from an Internet?
First, it’s really not “an” Internet – more like “the” Internet (hence the proper noun capitalization). Since everything on the internet is connected via protocols, it’s more of a singular web of information — hence the term “World Wide Web”.
The Internet is accessible to anyone with a connection and is typically done via a browser similar to the one you’re using now.