JS Interview Questions and Answers
JavaScript is a popular programming language that is used for front-end and back-end web development. If you’re looking to land a job as a JavaScript developer, you’ll need to be well-prepared for the interview process.
To help you prepare, we have compiled a list of the most commonly asked JavaScript interview questions and answers. This PDF contains 100 Q&A that cover topics such as JavaScript basics, DOM manipulation, event handling, asynchronous programming, closures, and more.
JavaScript Interview Questions PDF
By studying these questions and answers, you’ll be well-equipped to tackle any JavaScript interview with confidence. So, let’s dive in and start preparing for your next JavaScript interview!
Contents
- What is JavaScript?
- What are the data types in JavaScript?
- What is the difference between null and undefined?
- What is the DOM in JavaScript?
- What is an event in JavaScript?
- What is an anonymous function in JavaScript?
- What are closures in JavaScript?
- What is the difference between == and === in JavaScript?
- What is hoisting in JavaScript?
- What is the this keyword in JavaScript?
- What are the different ways to define a function in JavaScript?
- What is the purpose of the let keyword in JavaScript?
- What is the purpose of the const keyword in JavaScript?
- What are template literals in JavaScript?
- What are JavaScript promises?
- What is the async/await syntax in JavaScript?
- What are arrow functions in JavaScript?
- What is event delegation in JavaScript?
- What is the purpose of the map() function in JavaScript?
- What is the purpose of the filter() function in JavaScript?
- What is the purpose of the reduce() function in JavaScript?
- What is a callback function in JavaScript?
- What is the difference between let and var in JavaScript?
- What are JavaScript modules?
- What is object destructuring in JavaScript?
- What are JavaScript classes?
- What is inheritance in JavaScript?
- What are JavaScript getters and setters?
- What is the purpose of the try/catch statement in JavaScript?
- What is the difference between let and const in JavaScript?
- What is the purpose of the forEach() function in JavaScript?
- What is the purpose of the localStorage object in JavaScript?
- What are arrow functions? How are they different from regular functions?
- What is the purpose of the setTimeout() function in JavaScript?
- What is event bubbling in JavaScript?
- What is the purpose of the fetch() function in JavaScript?
- What is the difference between null and undefined?
- What is event propagation in JavaScript?
- What is the purpose of the Object.keys() function in JavaScript?
- What is the difference between null and undefined in JavaScript?
- What is the purpose of the addEventListener() method in JavaScript?
- What is the purpose of the parentNode property in JavaScript?
- What is the purpose of the querySelector() method in JavaScript?
- What is the purpose of the querySelectorAll() method in JavaScript?
- What is the difference between querySelector() and getElementById()?
- What is the difference between function declarations and function expressions in JavaScript?
- What is the purpose of the bind() method in JavaScript?
- What is the purpose of the call() method in JavaScript?
- What is the purpose of the apply() method in JavaScript?
- What is the purpose of the Array.isArray() method in JavaScript?
- What is event capturing in JavaScript?
- What is event delegation in JavaScript?
- What is the purpose of the startsWith() method in JavaScript?
- What is the purpose of the endsWith() method in JavaScript?
- What is the purpose of the includes() method in JavaScript?
- What is the purpose of the padStart() method in JavaScript?
- What is the purpose of the padEnd() method in JavaScript?
- What is the purpose of the charAt() method in JavaScript?
- What is the purpose of the charCodeAt() method in JavaScript?
- What is the purpose of the String.fromCharCode() method in JavaScript?
- What is the purpose of the JSON.stringify() method in JavaScript?
- What is the purpose of the JSON.parse() method in JavaScript?
- What is the purpose of the encodeURIComponent() function in JavaScript?
- What is the purpose of the decodeURIComponent() function in JavaScript?
- What is the purpose of the Math.random() function in JavaScript?
- What is the purpose of the Math.floor() function in JavaScript?
- What is the purpose of the Math.ceil() function in JavaScript?
- What is the purpose of the Math.round() function in JavaScript?
- What is the purpose of the Math.max() function in JavaScript?
- What is the purpose of the Math.min() function in JavaScript?
- What is the purpose of the Math.pow() function in JavaScript?
- What is the purpose of the Math.sqrt() function in JavaScript?
- What is the purpose of the Math.abs() function in JavaScript?
- What is the purpose of the Math.floor() and Math.random() functions together?
- What is the purpose of the Date() constructor in JavaScript?
- What is the purpose of the getFullYear() method in JavaScript Date objects?
- What is the purpose of the getMonth() method in JavaScript Date objects?
- What is the purpose of the getDate() method in JavaScript Date objects?
- What is the purpose of the getDay() method in JavaScript Date objects?
- What is the purpose of the getHours() method in JavaScript Date objects?
- What is the purpose of the getMinutes() method in JavaScript Date objects?
- What is the purpose of the getSeconds() method in JavaScript Date objects?
- What is the purpose of the getFullYear() and getMonth() methods together in JavaScript Date objects?
- What is the purpose of the setFullYear() method in JavaScript Date objects?
- What is the purpose of the setMonth() method in JavaScript Date objects?
- What is the purpose of the setDate() method in JavaScript Date objects?
- What is the purpose of the setHours() method in JavaScript Date objects?
- What is the purpose of the setMinutes() method in JavaScript Date objects?
- What is the purpose of the setSeconds() method in JavaScript Date objects?
- What is the purpose of the toLocaleString() method in JavaScript Date objects?
- What is the purpose of the toDateString() method in JavaScript Date objects?
- What is the purpose of the getTime() method in JavaScript Date objects?
- What is the purpose of the setTime() method in JavaScript Date objects?
- What is the purpose of the setTimeout() function in JavaScript?
- What is the purpose of the setInterval() function in JavaScript?
- What is the purpose of the clearTimeout() function in JavaScript?
- What is the purpose of the clearInterval() function in JavaScript?
- What is the purpose of the isNaN() function in JavaScript?
- What is the purpose of the isFinite() function in JavaScript?
- What is the purpose of the parseFloat() function in JavaScript?
Nu Of Pages
12 Pages