What is React JS?
React JS is a popular and open source Javascript library which is used to create UI (frontend) which is developed and managed by facebook. It allows developers to create fast, interactive and dynamic web pages. React JS developers break down their UI into reusable components and each components manages its own state and logic. Its primary goal is to making efficient and scalable front-end applications.
Key features of React JS (How it works?)
- Components: The applications of React JS are small, reusable components and each represents a part of the User Interface (UI) such as button, form or navigation bar. Each component is just like a small function that returns HTML code(JSX) and it also contain logic and styling. These components or parts combine to build more complex UIs. For example: if you’re building a shopping website, you have a component for a product listing, another for the shopping cart, and yet another for user reviews. This will make your code easier to reuse and manage.
- Virtual DOM: It uses a virtual DOM(Document Object Model), which is a copy of the real DOM. When we make any changes to our UI, react updates the real DOM, and only makes the necessary updates which makes it fast.
- One-way Data Binding: React js follows a unidirectional data flow. It means that data is passed from parent components to child components making it easier to track changes and manage the data flows.
- JSX (Javascript XML): In react, it uses a syntax called JSX, in which developers write HTML-like code directly in javascript. JSX makes the code clean and easier to understand which has a combo of both logic and design in one place/file for our efficiency. for example: const element = <h1>Hello, World!</h1>;
- Declarative Programming: React JS uses a style of programming where you just say what you want the user interface to look like, without worrying about how to make it work. It automatically updates the screen for you.
FAQs on React JS
1. Is React JS a framework or library?
React JS is Javascript library, not a framework because it focuses mainly on building user interfaces.
2. What is JSX is React JS?
JSX(JavaScript XML) is a syntax extension for Javascript used in React. It has HTML-like code directly within Javascript and is compiled to regular at runtime.
3. What is the difference between React and Angular?
Both React and Angular are used to build UIs. React is Javascript library that is specific on UI development but Angular is full-fledged framework.
4. What are Props in React JS?
Props are used to pass data from one component to another. They allow child components to receive dynamic values from their parent components.
5. What is State in React JS?
State refers to the internal data of a component that changes on time.
6. How do you manage forms in React?
There are some controlled components which manage forms where the input form elements’ values are tied to the component’s state.
7. What are React Hooks?
There are some special functions that allow you to use state and the react features in functional components are known as react hooks.
8. Is React JS SEO-friendly?
React JS itself is not SEO-friendly due to its client-side rendering. It can be more SEO-friendly by allowing search engines to crawl the content.
9. What are some popular alternatives of React JS?
There are some popular alternatives to React JS include:
- Angular: A framework by Google
- Vue.js: A progressive Javascript framework
- Svelte: A new framework that compiles components into efficient imperative code