Linux Filesystem Structure

Understanding the Linux filesystem is crucial for navigating and managing files effectively. Unlike Windows with drive letters (C:, D:), Linux has a single hierarchical tree starting from root (/).

The Root Directory

Everything in Linux starts from / (root):

/
├── bin     - Essential command binaries
├── boot    - Boot loader files
├── dev     - Device files
├── etc     - System configuration files
├── home    - User home directories
├── lib     - Essential shared libraries
├── media   - Mount points for removable media
├── mnt     - Temporary mount points
├── opt     - Optional application software
├── proc    - Process and kernel information
├── root    - Root user's home directory
├── sbin    - System binaries
├── srv     - Service data
├── sys     - System information
├── tmp     - Temporary files
├── usr     - User programs and data
└── var     - Variable data (logs, databases)

Important Directories Explained

/home - User Home Directories

Each user has a directory under /home:

/home/
├── alice/
├── bob/
└── user/

The ~ symbol is a shortcut for your home directory.

/etc - Configuration Files

System-wide configuration:

/etc/
├── hosts       - Hostname mappings
├── passwd      - User account info
├── hostname    - System hostname
└── ...

/var - Variable Data

Files that change frequently:

/var/
├── log/        - System logs
├── www/        - Web server files
└── tmp/        - Temporary files

Explore the Filesystem

Navigate through the filesystem using the terminal:

Paths: Absolute vs Relative

Absolute Paths

Start from root (/):

• /home/user/documents
• /etc/hosts
• /var/log/syslog

Relative Paths

Start from current directory:

• documents (if you're in /home/user)
• ../bob (go up one level, then to bob)
• ./script.sh (current directory)

Special Path Symbols

Symbol	Meaning
/	Root directory
~	Home directory
.	Current directory
..	Parent directory
-	Previous directory

Exercise: Understand Paths

Navigate to the /etc directory and list its contents:

Key Takeaways

• Linux uses a single hierarchical filesystem starting at /
• /home contains user directories
• /etc contains system configuration
• Absolute paths start with /, relative paths don't
• Use ~ for home, . for current, .. for parent directory