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JavaScript Interview Questions

  1. Definition
  2. Learn about JavaScript Engine (Chrome V8)
  3. https://www.freecodecamp.org/news/execution-context-how-javascript-works- behind-the-scenes/
  4. Map,WeakMap, set & Array
  5. Prototypal Inheritance
  6. Closure
  7. Hoisting
  8. Functional declaration vs function expression
  9. ES6 vs ES5, explain ES6 features
  10. Array methods like filter, reduce, find, map, forEach, sort etc.
  11. Learn sort method on numbers and string how it is used to sort numbers and strings
  12. String methods like split, join, indexOf, includes etc.
  13. Functions (very imp) methods: call, apply, bind
  14. Currying
  15. __proto vs prototype property
  16. Object.create()
  17. Default parameters in functions
  18. Prototype chain
  19. Reverse a string
  20. Find the intersection/union of two arrays
  21. Two sum problem
  22. Array flattening
  23. Objects, Object.freeze(), Object.seal(), Object.keys(), Object.values()
  24. Temporal dead zone
  25. Difference among let, var and const
  26. Debounce and throttling
  27. Memoization
  28. Web performance
  29. Web Accessibility
  30. Promises
  31. Callbacks, Callback Hell
  32. Event Loop, Call Stack, Callback queue
  33. OOP (Object Oriented Programming)
  34. ES6 features (Rest Operator, spread operator)
  35. Shallow Copy and Deep copy
  36. Object de-structuring, array de-structuring
  37. Aysnc Await
  38. Learn about function constructor vs classes
  39. This keyword and how it behaves differently with function and objects
  40. This keyword with arrow functions
  41. Arrow functions
  42. Event bubbling and event capturing
  43. Event delegation
  44. Sets, Maps
  45. Garbage collection (mark and sweep, reference counting algorithms)
  46. Stack and Queue (use of these in script execution)
  47. Scope Chaining
  48. Scoping like global scope, block scope and function scope (learn the order of these)
  49. Symbol
  50. Generator functions
  51. Design Patterns
    1. Command Pattern
    2. Factory Pattern
    3. Flyweight Pattern
    4. Mediator/Middleware Pattern
    5. Mixin Pattern
    6. Module Pattern
    7. Observer Pattern
    8. Prototype Pattern
    9. Provider Pattern
    10. Proxy Pattern
    11. Singleton Pattern
    12. Static Import Pattern