Explain how virtual DOM works?

Difficulty: 5/10

reconciliation, diffing algorithm, batch updates

Here's how the Virtual DOM works and how it aids in performance optimization in React:

1
Initial Render: When we create a React component, it generates a Virtual DOM representation of the component's structure and content. This Virtual DOM is essentially a JavaScript object tree, mimicking the actual structure of the HTML elements.
2
State and Props Changes: Whenever the state or props of a component change, React creates a new Virtual DOM representation of the component. This new Virtual DOM is then compared with the previous one.
3
Virtual DOM Reconciliation: React performs a process of reconciliation to compare the previous Virtual DOM with the new one. It identifies the differences between the two representations.
4
Minimal Updates: React calculates the minimal set of changes needed to bring the Virtual DOM in sync with the real DOM. Instead of directly updating the entire real DOM, React calculates and applies only the necessary changes.
5
Batching and Rendering: React batches multiple changes together and applies them in a single update to the real DOM. This reduces the number of times the real DOM is accessed and manipulated, resulting in better performance.

0-2 years experience