Javascript Interview Questions

1. How can we avoid Global variables?  
2. What are Closures?  
3. Why do we need Closures?  
4. Explain IIFE?  
5. What is the use of IIFE ?  
6. What is name collision in global scope ?  
7. IIFE vs Normal Function
8. What are design patterns?  
9. Which is the most used design pattern in JavaScript?  
10. What is module Pattern and revealing module pattern?  
11. How many ways are there to create JavaScript objects ?  
12. How can we do inheritance in JavaScript?  
13. What is prototype in JavaScript?  
14. Explain Prototype chaining?  
15. What is Let Keyword?  
16. Are Let variables hoisted?  
17. Explain Temporal Dead Zone?  
18. Let vs Var  
19. Tricky Question around Concatenation  
20. Explain class keyword
21. So with Class Keyword can we say Javascript is OO ?
22. What is difference between Class and Normal function?
23. Explain Arrow function?
24. When will you use an Arrow function?
25. Arrow functions vs Normal functions?
26. Does Arrow function have its own this ?
27. Explain Synchronous execution?
28. What is a call Stack in JavaScript ?
29. What is a blocking call?
30. How to avoid blocking calls ?
31. Synch vs Asynch ?
32. How can we do Asynch calls in Javascript ?
33. Explain threads ?
34. Explain Multi-threading ?
35. Is JavaScript Multi-threaded ?
36. Then how does Settimeout run
37. What is a WebAPI/Browser API ?
38. What is an Event loop and callback queue?
39. What is the output of the below code (Testing Eventloop and CallBack Queue) ?