Reading: Props and State - jacobwendt-401-advanced-javascript/cr-js-401d3 GitHub Wiki

Understanding React setState

• State can be anything.
• React components with state render UI based on that state.
• setState() is the only legitimate way to update state after the initial state setup.

Differences between functional and class-Components

• The most obvious one difference is the syntax. A functional component is just a plain JavaScript function which accepts props as an argument and returns a React element.