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Lal Sahab Yadav
Lal Sahab Yadav

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JavaScript Interview Questions and Answers

To help you prepare for your JavaScript interview Questions, here are the top 5 JavaScript interview questions and answers tailored for freshers.

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Q1. What is JavaScript, and what are its key features?
Ans: JavaScript is a scripting language primarily used for enhancing web pages with dynamic content and interactivity. It is lightweight and versatile, supporting various programming paradigms such as object-oriented and functional programming. Key features include dynamic typing, prototypal inheritance, and first-class functions.

Q2. What are the data types in JavaScript?
Ans: JavaScript has several built-in data types, including numbers, strings, booleans, null, undefined, and symbols (added in ES6). Additionally, objects and functions are considered reference types in JavaScript.

Q3. What is the difference between == and === operators?
Ans: The == operator performs type coercion, meaning it attempts to convert the operands to the same type before comparing them. On the other hand, the === operator, also known as the strict equality operator, compares both the value and the type of the operands.

Q4. What is hoisting in JavaScript?
Ans: Hoisting is a JavaScript behavior where variable and function declarations are moved to the top of their containing scope during the compilation phase. This means that you can access variables or functions before they are declared.

Q5. Explain the difference between let, const, and var.
Ans: var has function scope and can be redeclared and reassigned. let has block scope and can be reassigned but not redeclared. const has block scope and cannot be reassigned or redeclared.

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