React vs traditional JavaScript - Quick Revision & Key Differences

Recall & Review

beginner

What is the main difference between React and traditional JavaScript when building user interfaces?

React uses components to build UI in a structured and reusable way, while traditional JavaScript manipulates the DOM directly and often mixes HTML, CSS, and JS in less organized ways.

intermediate

How does React improve updating the user interface compared to traditional JavaScript?

React uses a virtual DOM to efficiently update only the parts of the UI that change, avoiding slow full page or large DOM updates common in traditional JavaScript.

beginner

What role do components play in React compared to functions in traditional JavaScript?

Components in React are like building blocks that manage their own content and state, making UI easier to build and maintain, unlike traditional JS functions which often just run code without UI structure.

beginner

Why is JSX important in React compared to traditional JavaScript?

JSX lets you write HTML-like code inside JavaScript, making UI code clearer and easier to understand, while traditional JavaScript requires manual DOM creation and manipulation.

intermediate

How does React handle state differently than traditional JavaScript?

React uses hooks like useState to keep track of data that changes over time and automatically updates the UI, whereas traditional JavaScript requires manual DOM updates when data changes.

What does React use to efficiently update the UI?

A CSS animations

B Direct DOM manipulation

C jQuery selectors

D Virtual DOM

React uses a virtual DOM to update only the parts of the UI that change, improving performance.

In React, what is JSX used for?

A Writing HTML-like code inside JavaScript

B Styling components

C Fetching data from APIs

D Managing browser cookies

JSX allows writing HTML-like syntax directly in JavaScript, making UI code easier to read and write.

Which of these is a key feature of React components?

A They run server-side only

B They manage their own state and UI

C They replace HTML tags in the browser

D They only handle CSS styling

React components manage their own state and UI, making them reusable and organized.

How does traditional JavaScript usually update the UI?

A By directly changing the DOM elements

B Using virtual DOM

C With React hooks

D Through JSX syntax

Traditional JavaScript updates the UI by directly manipulating DOM elements.

What React hook is commonly used to handle changing data in components?

A useEffect

B useContext

C useState

D useRef

useState is the React hook used to manage state and update the UI when data changes.

Explain how React's approach to building user interfaces differs from traditional JavaScript.

Think about how React organizes UI and updates it compared to manual DOM changes.

Describe the benefits of using React components over traditional JavaScript functions for UI development.

Consider how components help keep UI code organized and manageable.