1. What is Node.js? Explain its architecture.
2. What is the event loop in Node.js? How does it work?
3. What are Streams in Node.js?
4. What are the different types of Modules in Node.js?
5. What is process.nextTick() and how is it different from setImmediate()?
6. How does Node.js handle asynchronous operations?

Callback, Promises, and Async/Await.

1. What is the difference between require and import in Node.js?
2. How does error handling work in Node.js?

Try-catch, error-first callbacks.

1. What is the cluster module in Node.js?

Used for scaling an application using multiple processes.

1. What is the purpose of middleware in Node.js?

Express.js

1. What is Express.js and why is it used?
2. Explain middleware in Express.

Types: Built-in, Third-party, and Custom.

1. How can you handle errors in Express?