Facebook is not the Internet. Nor is Google. Nor is the World Wide Web
A common misconception — which companies like Facebook in particular are eager to encourage — is that the Internet is the same thing as the service(s) that one uses every day. It’s not. Facebook, Google and the Web are just various kinds of data-traffic that run on an underlying infrastructure. That infrastructure is the Internet.
A good way of thinking about this is a railway network. It has two main components. One is its infrastructure of tracks, signalling, points and stations. The other is the various kinds of traffic — TGV trains, intercity trains, stopping trains, goods trains, maintenance trains, etc. — that runs on the tracks.
So thinking that, say, Facebook is the Internet is like thinking that Virgin Trains is the railway system.
This is important because the Internet is much bigger and more important than any particular kind of data-traffic that runs on it. And it’s much freer and more open than anything provided by giant tech companies. It’s a public utility, not the private fiefdoms that they own and run.
Further reading
John Naughton, From Gutenberg to Zuckerberg: what you really need to know about the Internet, especially Chapter 2.