What is the Virtual DOM?

React is an absolute powerhouse when it comes to building dynamic user interfaces. But there’s one aspect of React that often gets overlooked, and it’s a doozy: the Virtual DOM.

You might be thinking, “Oh great, another boring technical term to add to my list,” but trust me, understanding the Virtual DOM is like finding the secret sauce to a Big Mac. It makes everything better.

So, what is the Virtual DOM exactly? It’s a lightweight representation of the actual DOM (Document Object Model) that React uses to update the user interface efficiently. Think of it like a personal assistant for your code. It keeps track of all the changes you make to the component’s state, and only updates the parts of the DOM that have been affected. This process is known as “reconciliation” and it’s what makes React so fast.

When a component’s state is updated, React first creates a new Virtual DOM tree based on the updated state. It then compares this new tree with the previous one and identifies the differences between the two. It then updates the actual DOM with these changes in the most efficient way possible.

Here’s an example of how this process works with functional components and hooks: