Object

Question 1

How many data types are there in JavaScript?

Answer 1

Eight

Seven of these data types are called primitive.

Question 2

What are primitive data types in JavaScript?

Answer 2

• String
• Number
• Boolean
• Undefined
• Null
• Symbol
• BigInt

Primitive data types contain only a single value.

Question 3

What are objects used for in JavaScript?

Answer 3

To store keyed collections of various data and more complex entities

Objects penetrate almost every aspect of the JavaScript language.

Question 4

How can an object be created in JavaScript?

Answer 4

• Using curly braces {…}
• Using the object constructor syntax: let user = new Object();

The curly braces are commonly used for object literals.

Question 5

What is a property in the context of a JavaScript object?

Answer 5

A ‘key: value’ pair

The key is a string (property name), and the value can be anything.

Question 6

What does an empty object represent in JavaScript?

Answer 6

An ‘empty cabinet’

It can be created using either object constructor or object literal syntax.

Question 7

Fill in the blank: An object can be created using ________ syntax.

Answer 7

object literal

This is commonly done using curly braces.

Question 8

True or false: A property in a JavaScript object has a key and a value.

Answer 8

TRUE

The key is also known as the name or identifier.