Navigating the Filesystem

Everything in Linux is a file — regular files, directories, devices, and even processes are represented in the filesystem. Understanding how the filesystem is organised and how to navigate it is the first essential skill.

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The Filesystem Hierarchy Standard (FHS)

Linux follows the Filesystem Hierarchy Standard, which defines a consistent directory structure:

Directory	Purpose
/	Root of the entire filesystem
/home	User home directories (e.g., /home/alice)
/root	Home directory for the root (superuser) account
/etc	System-wide configuration files
/var	Variable data — logs, caches, spool files
/tmp	Temporary files (cleared on reboot)
/usr	User programs, libraries, documentation
/bin	Essential user command binaries (ls, cp, mv)
/sbin	Essential system binaries (fdisk, iptables)
/opt	Optional third-party software
/dev	Device files (disks, terminals, USB)
/proc	Virtual filesystem exposing kernel and process info
/sys	Virtual filesystem for kernel device/driver info
/mnt	Temporary mount points
/media	Mount points for removable media (USB, CD)
/boot	Boot loader files and the kernel image
/lib	Essential shared libraries for /bin and /sbin

/
├── home/
│   ├── alice/
│   └── bob/
├── etc/
│   ├── ssh/
│   ├── nginx/
│   └── passwd
├── var/
│   ├── log/
│   └── www/
├── usr/
│   ├── bin/
│   ├── lib/
│   └── share/
└── tmp/

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Absolute vs Relative Paths

Absolute Paths

Start from the root (/) and specify the full location:

/home/alice/documents/report.txt
/etc/nginx/nginx.conf
/var/log/syslog

Relative Paths

Start from your current directory:

documents/report.txt      # relative to current directory
../bob/notes.txt           # go up one level, then into bob/notes.txt
./script.sh                # current directory

Special Directory References

Symbol	Meaning
.	Current directory
..	Parent directory
~	Home directory of the current user
~alice	Home directory of user alice
-	Previous directory (used with cd)

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Essential Navigation Commands

pwd — Print Working Directory

Shows your current location in the filesystem:

$ pwd
/home/alice

cd — Change Directory

Move between directories: