Introduction

In the previous chapters, we learned about the various methods we can use to fetch data from external APIs and how to include that data inside your React application. This process required you to send XMLHttpRequest(XHR) requests over the network, take the result, and store it in your component.

A web page is often composed of more than just a React app; for example, an application can be embedded in a website where there are various elements in a web page (including our React app) all working together, like different form elements or HTML components. With all these elements that live outside your React components, you might think: could we access these other elements that are not controlled by the React application itself?

This question leads to the following section. We actually can control these elements "living outside" of a React application through References(Refs).