Among all other javascript libraries, React.js stands out. It relies on reusable components, not templates, for UI development, allowing developers to render views where data changes over time. React applications are more scalable and more maintainable, making developers more efficient and users more satisfied. In this course, Eve Porcello introduces the history and basics of the React library and show how to use it to create two projects: a browser-based activity counter app and a simple website for displaying data drawn from an API. Along the way, learn how to set up your development environment, including helpful tools such as Babel and webpack; create new components; use props and state to pass data between components; use routes to map URLs to views; and organize projects with nested components and routes. By the end of the course, you'll understand the essentials of React.js and be able to start building your own browser-based projects.