Quizly - Daily Quiz To Test Your Javascript knowledge!

1. Which keyword is used to declare a variable in JavaScript?

A. var

B. let

C. const

D. All of the above

2. What will typeof null return in JavaScript?

A. ‘null’

B. ‘undefined’

C. ‘object’

D. ‘number’

3. Which of the following is NOT a JavaScript data type?

A. Number

B. Undefined

C. Float

D. Float

4. What does the === operator do?

A. Compares both value and type

B. Compares only value

C. Assigns a value

D. Checks for inequality

5. Which method converts JSON data to a JavaScript object?

A. JSON.parse()

B. JSON.stringify()

C. JSON.toObject()

D. JSON.convert()

6. What is the default value of an uninitialized variable in JavaScript?

A. null

B. undefined

C. 0

D. false

7. Which symbol is used for comments in JavaScript (single line)?

A.

B. // comment

C. * comment *

D. # comment

8. How do you write “Hello World” in an alert box?

A. msgBox(“Hello World”);

B. alertBox(“Hello World”);

C. alert(“Hello World”);

D. prompt(“Hello World”);

9. What will console.log(2 + "2") output?

A. 4

B. 22

C. NaN

D. Error

10. Which of the following is used to stop a loop in JavaScript?

A. stop

B. break

C. return

D. exit