1. What is Node.js?

2. What is npm?

3. What is Express.js?

4. What is middleware in Express?

5. How do you handle errors in Express?

6. What is a RESTful API?

7. What is CORS?

8. How do you connect to a MongoDB database in Node.js?

9. What is a promise in Node.js?

10. How do you read a file in Node.js?

11. What is the event loop in Node.js?

12. What is the difference between `require` and `import`?

13. What are callbacks?

14. What is the purpose of the `next()` function?

15. What is the difference between `var`, `let`, and `const`?

16. How do you implement authentication in a Node.js application?

17. What is JWT?

18. How do you validate user input in Node.js?

19. What is socket.io?

20. What is clustering in Node.js?

21. What are streams in Node.js?

22. How do you handle asynchronous code?

23. What is a template engine?

24. How do you implement logging in Node.js?

25. What is dotenv?

26. How do you test a Node.js application?

27. What is a microservice?

28. What is a reverse proxy?

29. How do you enable gzip compression in Express?

30. What is the purpose of `process.env`?

31. How do you create a simple web server in Node.js?

32. What is the difference between GET and POST requests?

33. How do you handle file uploads in Node.js?

34. What is a session?

35. What is the purpose of `cors` middleware?

36. How do you schedule tasks in Node.js?

37. What is a build tool?

38. What are environment variables?

39. What is rate limiting?

40. How do you implement security in a Node.js application?

41. What is a firewall?

42. What is middleware in Express?

43. How do you implement JWT authentication?

44. What is a callback in Node.js?

45. What is the purpose of `require()` in Node.js?

46. What is the Event Loop?

47. What is the purpose of `npm start`?

48. What are promises?

49. What is the difference between synchronous and asynchronous code?

50. How do you handle errors in Node.js?

51. What is a RESTful API?

52. What is the purpose of the `body-parser` middleware?

53. How do you connect to a MongoDB database?

54. What is socket.io?

55. How do you serve static files in Express?

56. What is the purpose of the `process` object?

57. What is a database migration?

58. What is the difference between NoSQL and SQL databases?

59. What is a templating engine?

60. How do you implement file system operations in Node.js?