Variables in JavaScript

This video tutorial introduces JavaScript variables, covering types like strings, integers, floating points, booleans, and objects. It explains how to declare, use, and output variables, including the concept of constants. The tutorial also demonstrates how to handle errors when trying to change constants and how to output object variables. The importance of coding exercises for learning is emphasized.

What is the purpose of using 'let' in JavaScript?

• To declare a constant

• To declare a class

• To declare a variable

• To declare a function

Which of the following is a string literal in JavaScript?

• 48

• 'Mark'

• true

• 3.89

What type of variable holds either true or false?

• Object

• String

• Boolean

• Integer

What is the primary use of a Boolean variable?

• To store text

• To store true or false values

• To store arrays

• To store numbers

Which of the following is NOT a type of variable in JavaScript?

• String

• Integer

• Character

• Boolean

Which operator is used for concatenation in JavaScript?

• -

• *

• +

• /

What is the result of trying to change a constant's value in JavaScript?

• The constant is deleted

• The program continues without changes

• The value changes successfully

• An error is thrown

What is a constant in JavaScript?

• A variable that can change

• A function that cannot be called

• A loop that runs indefinitely

• A value that cannot be changed once assigned

How does JavaScript handle outputting an object variable?

• It outputs the object as a string

• It throws an error

• It outputs the object in a comma-separated format

• It outputs nothing

What happens when you try to output an object variable using console.log?

• It outputs a null value

• It outputs an error message

• It outputs the first element only

• It outputs the entire object structure