Module 2: Filesystem Structure

The Linux filesystem is a hierarchical structure that organizes all files and directories on your system. Understanding this structure is essential for navigating and managing your Linux environment effectively.

Key Concept: In Linux, everything is treated as a file - even devices, processes, and system information are represented as files in the filesystem.

What You'll Learn in This Module

The Linux Filesystem Hierarchy Standard (FHS)
Purpose of key system directories
How to navigate the filesystem efficiently
The "everything is a file" philosophy in practice
File paths: absolute vs. relative

Lesson 2.1

Filesystem Hierarchy

Lesson 2.2

Everything is a File

Lesson 2.3

Navigation Basics

Module Objectives

By the end of this module, you will be able to:

Explain the purpose of major directories in the Linux filesystem
Navigate between directories using absolute and relative paths
Understand how devices and processes are represented as files
Use essential filesystem navigation commands
Locate different types of files on the system

Why This Matters

Understanding the filesystem structure is crucial because:

Efficiency: You'll quickly find files and directories without guessing
Troubleshooting: Many system issues involve locating the right configuration files
Security: Understanding permissions and locations helps secure your system
Development: Web development often involves working with specific directories

The Filesystem Hierarchy

Linux follows the Filesystem Hierarchy Standard (FHS), which defines the directory structure and contents. Here's an overview of the most important directories:

/ ├── bin/ # Essential user binaries ├── sbin/ # System binaries ├── etc/ # Configuration files ├── dev/ # Device files ├── proc/ # Process information ├── var/ # Variable data ├── home/ # User home directories ├── usr/ # User programs ├── tmp/ # Temporary files ├── opt/ # Optional software ├── boot/ # Boot loader files ├── lib/ # System libraries └── root/ # Root user home

Key Directories and Their Purposes

System Directories

/bin - Essential command binaries (ls, cp, mv, etc.)
/sbin - System administration binaries
/etc - System configuration files
/lib - Essential system libraries
/boot - Boot loader files and kernel

User Directories

/home - User home directories
/usr - User programs and data
/opt - Optional software packages
/tmp - Temporary files

Runtime Directories

/dev - Device files
/proc - Process and system information
/var - Variable data (logs, spool, etc.)
/run - Runtime data

Memory: Think of / as the trunk of a tree, with each directory as a branch. Understanding this tree structure helps you navigate efficiently.

Getting Started

Ready to explore the Linux filesystem? Start with the first lesson about the filesystem hierarchy structure.

Start with Filesystem Structure

Quick Terms to Know

Here are some terms we'll be using throughout this module:

Root Directory: The top-level directory (/)
Home Directory: Your personal directory (~)
Working Directory: Your current location
Path: The route to a file or directory
Mount Point: Where a filesystem is attached

Don't memorize everything! Focus on understanding the most common directories (/home, /etc, /var, /usr). You'll become familiar with others through practice.