Google’s biggest rival in internet search, says executive chairman Eric Schmidt, is Amazon. It is half true, anyway. Google has no global search rivals but (suppressed giggle) Microsoft. Yet shoppers looking for an item often go straight to browsing Amazon. So if search is to be equated with shopping, Amazon is a competitor.

And Google does not lie down for competitors. Google Express, the company’s shopping and delivery programme, has just launched a $95 annual membership with free delivery of household items in seven US cities. (Previously it was in four, and membership was free.) To a consumer, the service might feel like Amazon Prime. But as a business, it is closer to Uber or Alibaba.

Google runs a marketplace: consumers and merchants are brought together on a single information platform covering shopping, inventory, delivery planning, and payments (customers must use Google Wallet). Google does not own the delivery infrastructure. Instead, it pays courier companies to pick up items from stores, such as Target or Whole Foods, organise the items, and deliver them. Stores pay Google a commission on each sale, likely in the single-digits, AT Kearney estimates.