It's the gold standard IMO for an intro to React
Besides all the tutorials and articles, my list also has a section on "Community Resources", which points to other useful lists, newsletters, and more: https://github.com/markerikson/react-redux-links/blob/master... .
I'll also specifically highlight the Reactiflux community on Discord. It's a great place to ask questions, chat, and learn about React and related technologies. The invite link is at https://www.reactiflux.com .
React Resources: https://github.com/enaqx/awesome-react
These also helped to understand specific React concepts: https://medium.com/@dan_abramov/smart-and-dumb-components-7c... https://medium.com/@dan_abramov/mixins-are-dead-long-live-hi...
Related tech but also helped me learn React: https://brigade.engineering/what-is-the-flux-application-arc... https://egghead.io/courses/getting-started-with-redux
Also find some resources here: http://codecondo.com/reactjs-resources/