JS Interview Questions

Ques. : What is JavaScript?

Ques. : Differenciate between Java and JS.

Ques. : Which symbol is used for Comments in Javascript?

Ques. : Which company developed JS?

Ques. : Is JavaScript case sensitive?

Ques. : What are the different data types present in JS?

Ques. : Explain Hoisting in JS.

Ques. : Is it possible to break JavaScript Code into several lines?

Ques. : Differentiate between “ == “ and “ === “ operators in JS.

Ques. : What are Undeclared and Undefined variables in JS?

Ques. : What are the Prompt box, Alert box, and Confirm box in JS?

Ques. : Differentiate between var, let, and const keywords in JS.

Ques. : Why do we use the word “debugger” in JS?

Ques. : What are the primitive data types in JS?

Ques. : Explain JS is a dynamically typed language.

Ques. : What is the NaN property in JavaScript?

Ques. : What is negative Infinity in JS?

Ques. : Explain the use of “this” keyword in JS.

Ques. : What do you mean by Self Invoking Functions in JS?

Ques. : Explain call(), apply() and, bind() methods in JS.

Ques. : What is the difference between exec () and test () methods in JS?

Ques. : What is currying in JS?

Ques. : What are some advantages of using External JS?

Ques. : Explain Closures in JS.

Ques. : What are the main advantages of JS?

Ques. : What are callbacks in JS?

Ques. : What are the types of errors in JS?

Ques. : What is memorization in JS?

Ques. : What is the use of a constructor function in JS?

Ques. : What Is DOM & BOM concept?

Ques. :  What is the distinction between client-side and server-side JS?

Ques. :  What are arrow functions in JS?

Ques. : What are the rest parameter and spread operators?

Ques. : How many different methods are used to make an object in JS?

Ques. : What is the use of Promises in JS?

Ques. : What are classes in JS?

Ques. : What are Generator functions in JS?

Ques. : What is WeakSet in JS?

Ques. : Why do we use callbacks in JS?

Ques. : What is the Object Destructuring concept in JS?

Ques. : Explain whether JavaScript is a pass-by-reference or pass-by-value language.

Ques. : What is the role of deferred scripts in JS?

Ques. : In JS, how do you turn an Object into an Array []?

Ques. : How did the timers work in JS?

Ques. : How do you can submit a Form using JS?

Ques. : What is the difference between ViewState and SessionState?

Ques. : Does JS support Automatic type conversion?

Ques. : What is the use of Void (0)?

Ques. : What are the different types of errors in JS?