React technology is an open source JavaScript library for building user interfaces developed by Facebook (now known as Meta). It was created to facilitate the process of creating interactive, dynamic web pages and single-page applications. React allows developers to build large web applications that can change data without reloading the page.

Main features of React:

1. Component approach: React allows you to build applications using reusable components. Each component has its own state and logic, which facilitates efficient code management and separation.

2. Declarative style: React takes a declarative approach to describing user interfaces, which makes code more readable and easier to understand.

3. Virtual DOM: React uses the concept of virtual DOM to improve performance. Instead of updating the real DOM directly, React creates a virtual copy of the DOM and then does the math to determine the optimal way to update the browser's DOM.

4. Component Lifecycle: React components have several lifecycle methods that can be used to manage the process from rendering to component destruction.

5. JSX: JSX is a syntax extension for JavaScript that allows you to write HTML elements in JavaScript code. This makes the structure of the component clear and simplifies the development process.