Top 50 JavaScript MCQ's Questions and Answers (English and Hindi Language)

Summary

In this tutorial, Santosh Chauhan presents the 50 most important JavaScript questions commonly asked in exams. The video covers various JavaScript concepts, such as types of languages, writing code, accessing HTML elements, data types, operators, syntax, loops, and comments. It also delves into topics like variables, functions, and JavaScript frameworks, with practical examples and explanations. Aimed at learners, the tutorial provides clear answers to frequently asked questions, making it an invaluable resource for those preparing for JavaScript exams or looking to sharpen their programming skills.

Takeaways

• 😀 JavaScript is an object-oriented programming language, which is essential for building interactive websites.
• 😀 JavaScript's original name was 'LiveScript', but it was later renamed to 'JavaScript'.
• 😀 You can write JavaScript code in an external .js file or directly in an HTML document using the <script> tag.
• 😀 In JavaScript, the semicolon (;) is used to separate statements and terminate them.
• 😀 To include external JavaScript in an HTML document, you use the <script> tag with the 'src' attribute.
• 😀 JavaScript uses methods like 'getElementById' to access HTML elements by their ID.
• 😀 JavaScript supports both single-line (//) and multi-line (/* */) comments.
• 😀 Variables in JavaScript can be declared using 'var', 'let', or 'const', each serving different purposes.
• 😀 JavaScript is case-sensitive, meaning that uppercase and lowercase letters are treated as distinct.
• 😀 JavaScript provides different types of pop-up boxes like 'alert()', 'prompt()', and 'confirm()' to interact with users.

Q & A

What type of language is JavaScript?

JavaScript is an object-oriented programming language.

What was the original name of JavaScript?

The original name of JavaScript was 'LiveScript'.

How can we write JavaScript code in an HTML document?

JavaScript code can be written directly in an HTML document or in a separate JavaScript file.

Which symbol is used to separate JavaScript statements?

In JavaScript, a semicolon (;) is used to separate statements.

What is the correct syntax to include an external JavaScript file in an HTML document?

The correct syntax to include an external JavaScript file is <script src='filename.js'></script>.

Which method is used to access an HTML element by its ID in JavaScript?

The method to access an HTML element by its ID is 'getElementById()'.

What property is used to define the HTML content of an element with a specific ID?

The 'innerHTML' property is used to define the HTML content of an element with a specific ID.

Which keyword is used to declare variables in JavaScript?

In JavaScript, variables can be declared using 'var', 'let', or 'const'.

What does the 'alert' method do in JavaScript?

The 'alert' method is used to display a pop-up message in the browser.

What is the output when concatenating a string and a number in JavaScript?

When concatenating a string and a number, JavaScript converts the number to a string and joins them together.