The Art of Doing - Web Development for Beginners - JavaScript Data Types

This video tutorial introduces JavaScript basics, focusing on data types, variables, and the typeof operator. It covers creating and manipulating objects, as well as working with arrays, including adding and removing elements. The tutorial provides a practical approach to understanding these concepts through examples and console logging.

What is the purpose of using the 'defer' attribute in a script tag?

• To load the script only if the user clicks a button

• To load the script after the HTML content

• To load the script before the HTML content

• To load the script in a separate window

Which keyword is used to declare variables in JavaScript?

• var

• const

• let

• int

What data type is used to represent true or false values in JavaScript?

• Object

• Boolean

• Number

• String

What does the 'typeof' operator do in JavaScript?

• It changes the data type of a variable

• It creates a new variable

• It returns the data type of a variable

• It deletes a variable

What is the data type of a variable that has not been assigned a value?

• Boolean

• Undefined

• Null

• String

How do you create a new object in JavaScript?

• let myObject = {};

• let myObject = Object.create();

• let myObject = new Object();

• let myObject = Object();

Which method is used to add an element to the end of an array?

• push()

• append()

• insert()

• add()

What is the index of the first element in a JavaScript array?

• It depends on the array

• -1

• 0

• 1

Which method is used to remove the last element from an array?

• shift()

• remove()

• delete()

• pop()

What is the length of an array with elements ['a', 'b', 'c'] after using the pop() method once?

• 2

• 3

• 1

• 0