Facebook’s and eBay’s monopolies are very different from, and scarier than, Google’s. But what about Amazon?

People talk a lot about “Internet monopolies like Google and Facebook”, as though they are the same kind of thing. Even as astute a commentator as Tim Harford (alias “The Undercover Economist”) lumps them together in statements like “Google dominates search; Facebook is the Goliath of social media; Amazon rules online retail”.

But these “Internet monopolies” actually fall into completely different categories.

Google dominates search because it offers the best general-purpose search engine currently on the market.