How does Facebook/Mark Zuckerburg earn revenue?

[Lee]

There are a few ways that Facebook makes money. One way is by advertising. Another way is by selling users' comments and posts to companies to be used as advertisements. These are called "Sponsored Ads". The article I've referenced describes this in more detail.

There is also the "Promote and Share" feature where users can promote posts that others make to keep it on the top of the newsfeed. Of course, to do this, you will be charged a fee.

Also, Facebook now owns Instagram. Any photos posted can be sold by Facebook/Instagram to advertisers without compensating the original poster or without permission.