Summary  
This chapter explains how to perform synchronous and asynchronous file system operations, contrasting blocking methods that halt execution with non-blocking methods that use callbacks to keep code responsive.

General domain of usage  
File handling

The `fs` (File System) module in Node.js lets you work with files on your computer.
You can use it to read, write, delete, or modify files.

When working with files, you often need to choose between **synchronous** and **asynchronous** methods.

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- Synchronous file operations, such as `fs.readFileSync`, block the execution of your program until the file operation completes. This means that no other code runs while Node.js is reading or writing the file, which can slow down your application if the file is large or if you perform many such operations; 
- Asynchronous file operations, like `fs.readFile`, do not block the program. Instead, you provide a callback function that runs once the operation finishes. This allows Node.js to continue executing other code while it waits for the file system, making your applications more efficient and responsive, especially when dealing with many files or slow disks.

Which statements correctly describe the difference between `fs.readFileSync` and `fs.readFile` in Node.js

Master the modular structure that powers every Node.js project. Work with CommonJS and ES modules, explore Node's core utilities for file and system operations, and manage external dependencies through npm. Build a clear understanding of how modular code, system tools, and packages connect to create efficient, maintainable Node.js applications.

Understand how Node.js organizes code through its modular architecture. Explore how modules are loaded, shared, and managed using the CommonJS system, and apply exporting, importing, and path resolution techniques to structure scalable projects.

Move beyond CommonJS by adopting modern ES module syntax and combining it with Node's built-in capabilities. Work with the fs, path, and other core modules to manage files, directories, and system operations while maintaining clean, modular code.

Integrate system utilities and external dependencies to extend application functionality. Access system information through the os module and manage third-party libraries using npm for efficient package installation, updates, and dependency control.

Working with the fs Module

Awesome!

Working with the fs Module