JavaScript

Question 1

What is an object in JavaScript?

Answer 1

An object in JavaScript is a data type that represents a collection of data and methods.

Question 2

What is an array in JavaScript?

Answer 2

An array in JavaScript is a data type that represents a list of values.

Question 3

What is a constant in JavaScript?

Answer 3

A constant is a symbol that is assigned once when the program starts and never changes. Constants are useful to specify fixed values such as defining the constant PI to be 3.14159265, or COMPANY_NAME to hold the name of your company.

Question 4

What is the scope of a let variable?

Answer 4

The scope of a let variable is the block in which it is declared.

This means that a let variable can only be accessed within the block where it is declared.

Question 5

What is the difference between var and let in JavaScript?

Answer 5

var variables are global by default, while let variables are block scoped.

var variables can be re-assigned, while let variables cannot be re-assigned after they are initialized.

Question 6

What is the difference between global scope and local scope?

Answer 6

Global scope refers to the ability of a variable to be accessed from anywhere in the code. Local scope refers to the ability of a variable to be accessed only from within the function it is declared in.

Question 7

Can a global variable be accessed inside a function?

Answer 7

Yes, a global variable can be accessed inside a function.

Question 8

Can a local variable be accessed outside of the function it is declared in?

Answer 8

No, a local variable cannot be accessed outside of the function it is declared in.