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25 uniquely designed questions just for you to evaluate your skills in Javascript Basics quiz. Are you ready to challenge yourself and explore more? Let's get started and see how much you can score out of 25.

Test your knowledge of JavaScript basics with this interactive quiz. Explore JavaScript data types, operators, functions, and more in web development

Please feel free to report any corrections if you come across any inaccuracies or errors. Your feedback is valuable in maintaining the accuracy of our content.

Questions

1. What does JavaScript primarily allow you to do in web development?
Answer: Add interactivity and behavior to web pages
Explanation: JavaScript is primarily used to add interactivity and behavior to web pages, making them dynamic.Report for correction
2. Which of the following is NOT a valid JavaScript data type?
Answer: Character
Explanation: JavaScript does not have a data type called "Character." Instead, characters are represented as strings.Report for correction
3. How do you comment a single line of code in JavaScript?
Answer: // This is a comment
Explanation: In JavaScript, a single-line comment is created using "//."Report for correction
4. Which keyword is used to declare a variable in JavaScript?
Answer: var
Explanation: The "var" keyword is used to declare variables in JavaScript.Report for correction
5. What will be the result of the following code , console.log(5 + "5");?
Answer: "55"
Explanation: JavaScript performs type coercion, so it converts the number 5 to a string and concatenates it with the string "5."Report for correction
6. Which operator is used to compare two values for equality without considering their data types?
Answer: ==
Explanation: The double equals (==) operator is used for loose equality comparison.Report for correction
7. What is the correct way to declare a function in JavaScript?
Answer: var myFunction = function() {}
Explanation: The correct way to declare a function in JavaScript is to use the "var" keyword followed by the function name and its definition.Report for correction
8. How do you check the length of an array in JavaScript?
Answer: array.length
Explanation: To check the length of an array in JavaScript, you use the "length" property.Report for correction
9. Which of the following statements is used to exit a loop prematurely in JavaScript?
Answer: break
Explanation: The "break" statement is used to exit a loop prematurely in JavaScript.Report for correction
10. What does the typeof operator return for an undefined variable?
Answer: "undefined"
Explanation: The typeof operator returns "undefined" for an undefined variable.Report for correction
11. What is the result of the expression 5 > 3 && 2 < 4?
Answer: true
Explanation: The && operator returns true if both conditions are true, which is the case here.Report for correction
12. How can you convert a string to an integer in JavaScript?
Answer: parseInt()
Explanation: You can use the parseInt() function to convert a string to an integer in JavaScript.Report for correction
13. What is the purpose of the setTimeout() function in JavaScript?
Answer: To delay the execution of a function
Explanation: The setTimeout() function is used to delay the execution of a function by a specified number of milliseconds.Report for correction
14. What is an anonymous function in JavaScript?
Answer: A function with no name
Explanation: An anonymous function is a function with no name.Report for correction
15. Which of the following is the correct way to write a JavaScript array?
Answer: [1, 2, 3, 4]
Explanation: The correct way to write a JavaScript array is to use square brackets and separate elements with commas.Report for correction
16. What is the result of the expression 2 + "2"?
Answer: "22"
Explanation: JavaScript performs type coercion and converts the number 2 to a string before concatenating it with "2."Report for correction
17. What does the NaN value represent in JavaScript?
Answer: Not a Number
Explanation: NaN stands for "Not a Number" and represents an unrepresentable value in JavaScript.Report for correction
18. What is the purpose of the else statement in JavaScript?
Answer: To specify an alternative condition
Explanation: The else statement is used to specify an alternative condition to be executed if the initial condition is false.Report for correction
19. Which built-in object is used to display messages in a pop-up box in JavaScript?
Answer: alert
Explanation: The alert method is used to display messages in a pop-up box in JavaScript.Report for correction
20. What does the this keyword refer to in JavaScript?
Answer: The current function
Explanation: In JavaScript, the this keyword refers to the current function or context.Report for correction
21. Which statement is used to throw an exception in JavaScript?
Answer: throw
Explanation: The throw statement is used to throw an exception in JavaScript.Report for correction
22. What is the purpose of the forEach method in JavaScript?
Answer: To loop through the elements of an array
Explanation: The forEach method is used to loop through the elements of an array and perform a specified action for each element.Report for correction
23. Which operator is used for strict equality comparison in JavaScript?
Answer: ===
Explanation: The triple equals (===) operator is used for strict equality comparison, which checks both value and data type.Report for correction
24. What does the localStorage object in JavaScript allow you to do?
Answer: Store key-value pairs in the browser
Explanation: The localStorage object in JavaScript allows you to store key-value pairs in the user's web browser.Report for correction
25. Which function is used to remove an item from the end of an array in JavaScript?
Answer: pop()
Explanation: The pop() function is used to remove an item from the end of an array in JavaScript.Report for correction