Overview of ReactJs

ReactJS is an open-source front-end library. ReactJS is based on components. Components are the building block of ReactJS. Basically, the component is a JavaScript function or class which can take input and returns React Element that describes UI or output.

ReactJS uses virtual DOM to view data.

Virtual DOM is a programming concept where an ideal, or "virtual" representation of UI is kept in memory and synced with real DOM. Virtual DOM is fast because it only changes individual DOM elements instead of reloading the complete DOM every time.

WebPack: Webpack is a static module bundler, the main purpose is to bundle javascript files for usage in a browser. When WebPack processes your application, it internally bundles a dependency graph that maps every module your project needs and generates one or more bundles.