React JS Basics

Demand for React developers is skyrocketing, which means that having knowledge of this library is definitely going to be worth it! Some of the popular websites built using ReactJS include Dropbox, Netflix, and Instacart – and the list goes on.

Now, the common question that comes to everyone's mind is do we really need a JavaScript library, just for creating user interfaces? We can do the same using just HTML and CSS, right?

So what makes React so popular rather than just using vanilla HTML, CSS, and JavaScript? For that, let's first look at the 2 main features of React:

Of course there is more to React than this, but we'll focus on these two features here. Before moving on and learning more about these features, we must clearly understand the browser DOM.

What is the DOM?

The DOM (Document Object Model) represents the web page as a tree structure. Any piece of HTML that we write is added as a node, to this tree.

With JavaScript, we can access any of these nodes (HTML elements) and update their styles, attributes, and so on. This means that the DOM enables JavaScript to access and modify the web page easily.

Now, any tree must have a root node, right? Here, the root node is document. Are you wondering where this document node came from? Well, it's part of the browser. Any HTML tag you write is going to be a direct or indirect child of the root node document ⁠ ⁠Post source: