Summary
The goal of this chapter was to introduce you to the substantial changes in React 16. Remarkably, there are almost no compatibility issues with the prior React release. This is because most of the changes were internal and didn't require changes in the API. A couple of new features were added as well.
The headline of React 16 is its new reconciliation internals. Rather than trying to reconcile everything any time a component changes state, the reconciliation work is now broken into smaller units. These units can be prioritized, scheduled, paused, and resumed. In the near future, React will take full advantage of this new architecture and start rendering units of work asynchronously.
You also learned how to use the new error boundary functionality in React components. Using error boundaries allows you to recover from component errors without taking down the entire application. Then, you learned that React components can now return collections of components. This is just like when you render a collection of components. Now you can do this directly from components. Finally, you learned how to render components to nonstandard locations using portals.
In the next chapter, you'll learn how to build reactive components.
