📁 Directory Navigation

The Big Three

Three commands will get you anywhere:

• pwd — Print Working Directory (where am I?)
• cd — Change Directory (go somewhere)
• ls — LiSt (what’s here?)

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pwd — Where Am I?

pwd
# /home/user/Documents

The output is your absolute path — your exact location in the filesystem tree.

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cd — Change Directory

Basic Usage

cd /etc              # Go to /etc (absolute path)
cd Documents         # Go to Documents folder (relative path)
cd ..                # Go up one level
cd ../..             # Go up two levels
cd ~                 # Go to home directory
cd                   # Also goes home (shortcut)
cd -                 # Go to previous directory

Path Building

# If you're in /home/user
cd Documents/Work/Projects
# Now you're in /home/user/Documents/Work/Projects

cd ../../Personal
# Now you're in /home/user/Documents/Personal

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ls — List Contents

Basic Usage

ls                   # List files and directories
ls /etc              # List specific directory
ls -l                # Long format (details)
ls -a                # Show hidden files (.*)
ls -la               # Long format + hidden files
ls -lh               # Human-readable sizes (KB, MB, GB)
ls -lt               # Sort by time (newest first)
ls -lS               # Sort by size (largest first)
ls -R                # Recursive (all subdirectories)

Understanding Long Format

-rw-r--r-- 1 user group  4096 Dec 30 10:30 document.txt
└────┬────┘ │ └──┘ └───┘ └──┘ └────┬─────┘ └─────┬─────┘
     │      │   │    │     │       │             │
  perms   links owner group size   date        name

Hidden Files

Files starting with . are hidden by default:

ls -a
.bashrc  .config  Documents  Downloads  .ssh

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Practical Navigation Patterns

Jumping Around

# Save location, do something, return
pushd /var/log      # Save current dir, go to /var/log
# do stuff...
popd                # Return to saved location

Tab Completion

cd /ho[TAB]         # Completes to /home/
cd /home/u[TAB]     # Completes to /home/user/
ls /etc/pas[TAB]    # Completes to /etc/passwd

Wildcards

ls *.txt            # All .txt files
ls *.{jpg,png}      # All .jpg and .png files
ls file?            # file1, file2, fileA, etc.
ls [abc]*           # Files starting with a, b, or c

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tree — Visual Directory Structure

Not installed by default, but very useful:

sudo apt install tree

tree                # Current directory tree
tree -L 2           # Only 2 levels deep
tree -d             # Directories only
tree /etc -L 1      # /etc, 1 level

Output:

.
├── Documents
│   ├── report.pdf
│   └── notes.txt
├── Downloads
└── Pictures
    ├── vacation
    └── family

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Try It!

Use the terminal below to practice navigation:

Exercises:

1. Find out where you are (pwd)
2. List everything including hidden files (ls -la)
3. Navigate to /etc and back home
4. Use cd - to toggle between two directories
5. Try tab completion!

Try it: navigate the filesystem

The tree on the right redraws as you cd and ls. Goal: reach /etc and list it.