React is a JavaScript library designed for building user interfaces, created by Jordan Walke at Facebook. It was first introduced in 2013 and has since gained wide popularity among developers worldwide. The main purpose of React is to simplify the process of developing complex and interactive web applications.
Basic Principles of React Components: React applications are built from components, which are isolated pieces of code that have their own state and logic. Components can be reused in different parts of the application, increasing modularity and facilitating code maintenance.
JSX: JSX is a syntax similar to HTML that allows writing component structure in JavaScript. This enables developers to easily create user interfaces, which is more intuitive and readable than using plain JavaScript.
Virtual DOM: React uses the concept of a virtual DOM, where every change in the user interface first occurs in a virtual copy of the actual DOM. After determining the most efficient way to update, changes are applied to the real DOM, minimizing DOM manipulations and improving application performance.
State and Component Lifecycle Component State: Each component can have its own state, which influences what is displayed on the screen. The state can change in response to events such as mouse clicks or user inputs.
Lifecycle: React components go through several lifecycle phases – from initialization to updates and removal from the DOM. Developers can intervene in these phases using special lifecycle methods such as componentDidMount, componentDidUpdate, and componentWillUnmount.
Hooks
React 16.8 introduced a new feature called "hooks", which allows developers to use states and other React features without writing classes. For example, useState and useEffect are two basic hooks that enable working with states and effects without classes.
Practical Applications
React is widely used for developing single-page applications (SPAs), where users can interact with the application without the need to load new pages. Due to its efficiency and flexibility, it is also commonly used in large corporate projects and popular web services such as Instagram and Airbnb.
React remains a significant and dynamically evolving library in the JavaScript ecosystem. With its help, developers can efficiently create user-friendly, fast, and interactive web applications. Its modularity, combination with other libraries and tools, and extensive community of users and developers make it an excellent choice for modern Web development.
