This repository contains my learnings and experiments while exploring Advanced Node.js concepts.

• Node.js is a JavaScript runtime built on Google’s V8 engine.
• It acts as a bridge between JavaScript and lower-level system code by combining:
  • JavaScript (the language we write in)
  • V8 (JavaScript engine that compiles JS to machine code)
  • libuv (library that provides event loop, async I/O, and thread pool)
  • C++ bindings (for system-level operations)

• V8 is the default engine used by Node.js.
• Other JavaScript engines include:
  • Chakra (used by Microsoft Edge)
  • SpiderMonkey (used by Firefox)

• Explored how fs.readFile (asynchronous) works under the hood using libuv.
• Compared with fs.readFileSync (synchronous).
• Learned how Node.js internally calls C++ code for system-level file operations.
• Also checked OS-level documentation related to file system operations.

• Node.js appears single-threaded to developers because JavaScript runs on a single main thread.
• Under the hood, Node.js uses a thread pool (via libuv) for operations like:
  • File system tasks
  • Network requests
  • Cryptography
• This makes Node.js asynchronous and efficient.

• Learned how libuv manages a pool of worker threads.
• Tasks like I/O or heavy computations are delegated to the thread pool while the main thread stays free.

• Understood the event-driven architecture of Node.js.

• Studied how the event loop manages execution with:

  • Call Stack
  • Callback Queue / Task Queue
  • Microtask Queue (Promises, process.nextTick)
  • Web APIs
  • RAF Queue (requestAnimationFrame in browsers)

• Solved tough questions on:

  • Execution order of callbacks, promises, and microtasks.
  • Visualization of how the event loop cycles through tasks.

Through this learning process, I understood:

• How Node.js connects JavaScript with C++ through V8 and libuv.
• The difference between synchronous vs asynchronous execution.
• Why Node.js is single-threaded in JavaScript but multi-threaded under the hood.
• The event loop and how it makes Node.js non-blocking and scalable.

• Explore Streams & Buffers in Node.js.
• Learn Cluster & Worker Threads for scaling applications.
• Deep dive into Node.js performance optimization.