1. In Node.js, what is the purpose of the res object in an HTTP request handler function?
2. What HTTP methods are commonly used in RESTful APIs to perform CRUD (Create, Read, Update, Delete) operations on resources?
3. Which Node.js function is used to add a callback to the "next tick queue" for execution in the next iteration of the event loop?
4. What is a "memory leak" in the context of Node.js performance?
5. In the context of Node.js performance, what is "caching"?
6. In Node.js RESTful APIs, what is the purpose of the HTTP PUT method?
7. Which Node.js testing library is commonly used for E2E testing of web applications?
8. Which tool is commonly used for memory profiling in Node.js applications?
9. In Node.js, how is the connection to a PostgreSQL database typically established using the pg module?
10. Which JavaScript feature introduced in ES6 (ECMAScript 2015) is commonly used for handling asynchronous code in a more readable and maintainable way in Node.js?
11. Which Node.js module is commonly used for connecting to MongoDB databases?
12. Which built-in debugging tool is available in Node.js for inspecting code execution and troubleshooting?
13. Which testing framework is commonly used for unit testing in Node.js?
14. What is asynchronous programming in Node.js?
15. Which HTTP status code should be returned when a requested resource is not found in a Node.js web application?
16. What is a key advantage of using streams in Node.js for I/O operations?
17. In Express.js, how is routing typically defined for handling HTTP requests?
18. What is the primary advantage of using a RESTful API design in Node.js?
19. What is the purpose of the WebSocket.on('message') event in Node.js WebSocket communication?
20. Which Node.js module is commonly used for connecting to MySQL databases?