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Piyush Kumar Singh
Piyush Kumar Singh

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Top 30 most asked JavaScript Questions in Interviews.

Reference : JavaScript

  1. What are the different data types in javascript?

  2. Explain hoisting in js.

  3. Why do we use word "debugger" in js?

  4. Difference between "==" and "===" operator.

  5. Difference between "var" and "let" keyword in js.

  6. Explain Implicit type coercion in js.

  7. Is js a statically typed or dynamically typed language?

  8. What is NaN property in js?

  9. Explain pass by value and pass by reference in js.

  10. What is an Immediately invoked function in js?

  11. Explain higher order function in js.

  12. Explain "this" keyword.

  13. What do mean by self invoking function?

  14. Explain call(), apply() and bind() methods.

  15. What is the difference between exec() and test() in js?

  16. What is currying in js?

  17. Explain different types of scope in js.

  18. Explain closures in js.

  19. Mention some advantages of js.

  20. What are callbacks in js?

  21. What is memoization?

  22. What is the use of constructor function in js?

  23. What is DOM?

  24. What is BOM?

  25. What is the difference between client side and server side js?

  26. What are arrow functions?

  27. What is rest parameter and spread operator?

  28. What is the use of promise in js?

  29. What are classes in js?

  30. What are generator functions?

Other References :

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