Google

Google started in 1998 as a search engine built by two Stanford students, Larry Page and Sergey Brin. Their idea was to rank web pages by how many other pages linked to them, which gave much better results than the search engines of the time. Since 2015 Google is part of Alphabet, a parent company that also holds other bets such as Waymo, the self-driving car business.

Most people never pay Google directly, and yet it is one of the largest companies in the world. The trick is advertising: Search, YouTube, Maps, Gmail, Chrome and Android are free, billions of people use them every day, and businesses pay to show ads next to what those people search for or watch. Because a search says exactly what someone wants right now ('plumber near me'), those ads are unusually valuable, and ads still bring in most of the company's revenue.

On top of that it sells things directly. Google Cloud rents computing, storage and data tools to companies, competing with AWS and Microsoft Azure. Google DeepMind, its AI lab, builds the Gemini models, and Google designs its own AI chips, called TPUs. It also sells Pixel phones and other devices, and takes a share of the sales in the Play Store, the app store of Android.