What is React?
React, also known as React.js or ReactJS, is an open-source JavaScript
library for building user interfaces or UI components. It was
developed and is maintained by Facebook. React is widely used for
creating single-page applications (SPAs) where user interfaces need to
be dynamic and interactive. It allows developers to build reusable UI
components and efficiently manage the state of an application.
Key features and concepts of React include:
-
Component-Based Architecture:React follows a
component-based architecture, which means that user interfaces are
composed of small, reusable components. Each component is
responsible for rendering a part of the user interface, and these
components can be nested within each other to build complex UI
structures.
-
Virtual DOM: :React uses a virtual DOM (Document
Object Model) to improve performance. Instead of directly
manipulating the browser's DOM for every change, React creates a
virtual representation of the DOM in memory. When changes occur,
React calculates the minimal number of updates needed and then
applies them to the actual DOM, reducing the amount of work the
browser needs to do.
-
JSX (JavaScript XML): React introduces JSX, a
syntax extension for JavaScript that allows developers to write
HTML-like code within their JavaScript files. JSX makes it easier to
describe the structure of UI components and is later transpiled to
regular JavaScript by tools like Babel.ion persistently even when
the user closes the browser.
