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1. What is the difference between the operators '==' and '==='?
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2. What is an ECMAScript?
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3. What is DOM?
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4. What is the difference between innerHTML and innerText?
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5. What is the difference between null and undefined in JavaScript?
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6. How could you set a prefix before everything you log?
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7. What are falsy and truthy values?
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8. How do you check if an object is an array or not?
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9. What is the difference between the postfix i++ and prefix ++i increment operators?
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10. What is the instanceof operator in JavaScript?
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11. What would be the result of 3+2+”7″?
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12. What is AJAX?
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13. Is ‘false’ false?
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14. lock You have a for loop if you have setTimeout inside it. If log the loop counter inside setTimeout, what will be logged?
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15. lock What is the difference between slice and splice?
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16. lock What is the default unit of difference of two dates?
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17. lock What is hoisting in JavaScript?
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18. lock What types of functions does JavaScript support?
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19. lock What is the difference between the substr() and substring() functions in JavaScript?
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20. lock How would you swap two numbers without using a temporary variable?
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21. lock What are all the types of Pop up boxes available in JavaScript?
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22. lock How many ways we get the element in javascript?
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23. lock What kind of loops are in JavaScript?
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24. lock What is the difference between JSON.stringify and JSON.parse?
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25. lock How to handle exception in JavaScript?
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26. lock What is the difference between undeclared and undefined variables?
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27. lock Name some Javascript functions used to convert non numerical values into numbers.
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28. lock What is a closure in Javascript?
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29. lock What does isNaN function do?
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30. lock What are the different types of errors in JavaScript?
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31. lock How to access JSON object in JavaScript?
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32. lock What is the different between Statically typed and Dynamically Typed?
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33. lock How to check function exists before calling it?
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34. lock What is the difference between window.onload and onDocumentReady?
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35. lock How To Remove All Odd Numbers In An Array Using Javascript?
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36. lock What is the difference between ‘Function’ and ‘function’?
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37. lock How would you reverse a string in JavaScript?
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38. lock What is Hoisting?
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39. lock What is the difference between JSON.stringify and JSON.parse?
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40. lock What is the difference between window, screen, and document in JavaScript?
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41. lock What is the difference between the function declarations below?
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42. lock What is the only value not equal to itself in JavaScript?
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43. lock Difference between: function Person(){}, var person = Person(), and var person = new Person()?
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44. lock How to get array of object property value to a new array?
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45. lock Explain what a callback function is and why do we need?
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46. lock Can you name two programming paradigms important for JavaScript app developers?
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47. lock When is prototypal inheritance an appropriate choice?
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48. lock What is prototypical inheritance and how useful is it?
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49. lock What does a JavaScript function result when it has no return statement?
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50. lock What is the drawback of creating true private methods in JavaScript?
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51. lock What are promises and how they are useful?
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52. lock How to check whether a key exist in a JavaScript object or not?
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53. lock What does 0.1 + 0.2 === 0.3 evaluate to?
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54. lock What's the difference between JavaScript, JScript & ECMAScript?
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55. lock Explain the difference between a static method and an instance method.
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56. lock What is the only value not equal to itself in JavaScript?
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57. lock What is the difference between synchronous and asynchronous code in JavaScript?
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58. lock Why does 3 + true = 4?
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59. lock Write code to sum a property value in an array.