JavaScript Interview Questions and Answers

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JavaScript interview questions with answers


Knowing JavaScript and still not able to crack interviews , then you are at the right place. :-)


JavaScript Interview Questions and Answers Part:- 1

  • 1. Why do we call javascript as dynamic language
  • 2. how does javascript determine data types ?
  • 3. What is typeof ?
  • 4. How to check data type in javascript ?
  • 5. What are different datatypes in Javascript ?
  • 6. Explain Undefined Data types ?
  • 7. What is Null ?
  • 8. Differentiate between Null and Undefined ?
  • 9. Explain Hoisting ?
  • 10. Are Javascript initialization hoisted ?
  • 11. What are global variables ?
  • 12. What are the issues with Global variables ?
  • 13. What happens when you declare variable with out VAR ?
  • 14. What is Use Strict ?
  • 15. How to force developers to use Var keyword ?
  • 16. How can we handle Global Variables ?
  • 17. How can we avoid Global variables ?
  • 18. What are Closures ?
  • 19. Why do we need Closures ?
  • 20. Explain IIFE ?
  • 21. What is the use of IIFE ?
  • 22. What is name collision in global scope ?
  • 23. IIFE vs Normal Function
  • 24. What are design patterns ?
  • 25. Which is the most used design pattern
  • 26. What is module Pattern and revealing module pattern ?
  • 27. How man ways are there to create Javascript objects ?
  • 28. How can we do inheritance in Javascript ?
  • 29. What is prototype in Javascript ?
  • 30. Explain Prototype chaining ?
  • 31. What is Let Keyword ?
  • 32. Are Let variables hoisted ?
  • 33. Explain Temporal Dead Zone ?
  • 34. Let vs Var
  • 35. String Concantentation and Arthimetic puzzle

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