JavaScript Mastery from Zero to Hero - Prepare for Coding Interviews - What Are Datatypes and Variables in Programming P

The video tutorial introduces the eight data types in JavaScript: undefined, null, booleans, strings, symbols, numbers, objects, and arrays. It explains the differences between undefined and null, and how data types can be used as variables. The tutorial also covers how to declare variables using the 'var' keyword and provides an introduction to strings and numbers, emphasizing their role in programming. The video concludes with a brief overview of the key lessons and a preview of the next video, which will focus on practical examples.

Which of the following is NOT one of the eight data types in JavaScript?

• Symbol

• Boolean

• Object

• Integer

What is the difference between undefined and null in JavaScript?

• Undefined is a value, null is a type

• Undefined means a variable is not declared, null means it is declared but empty

• Undefined means a variable is declared but not assigned, null means it is assigned to nothing

• Undefined is a type, null is a value

What is the primary purpose of using variables in programming?

• To create loops

• To store data values

• To manage memory

• To define functions

Why do programmers prefer using 'var' instead of 'variable' in JavaScript?

• It is more secure

• It saves time and effort

• It is a convention

• It is more readable

Which keyword is used to declare a variable in JavaScript?

• var

• const

• let

• int

How are strings defined in JavaScript?

• Using square brackets

• Using single or double quotations

• Using parentheses

• Using curly braces

In JavaScript, what does a string store?

• Objects

• Boolean values

• Characters

• Numbers