Your First Commands

Let’s learn your first five commands. Each one does exactly one thing — that’s the Unix philosophy.

pwd — Print Working Directory

What it does: Shows where you are in the filesystem.

Try it now: Type pwd and press Enter.

You should see /home/user. That’s your home directory — the starting point for everything you do.

When AI tools use it: AI assistants often run pwd to figure out where they are before doing anything else.

whoami — Who Am I?

What it does: Prints your username.

Try it now: Type whoami

You’ll see user. Simple. On a real system, this tells you which account you’re using — important for knowing what permissions you have.

echo — Print Text

What it does: Prints whatever text you give it.

Try it now: Type echo "Hello, terminal!"

echo might seem basic, but it’s incredibly useful:

• Writing text to files: echo "hello" > file.txt
• Checking variable values: echo $HOME
• Building scripts that output messages

When AI tools use it: AI assistants use echo with > and >> to create and edit files — you’ll learn about this in Module 5.

clear — Clear the Screen

What it does: Clears all the text from the terminal.

Try it now: Type clear

Everything disappears! Don’t worry — nothing is deleted. Your files are untouched. It just cleans up the display.

Shortcut: Press Ctrl+L for the same effect.

history — Command History

What it does: Shows all the commands you’ve typed in this session.

Try it now: Type history

You’ll see a numbered list of everything you’ve entered. This is useful for:

• Remembering what you did
• Re-running a previous command
• Understanding what an AI tool has been doing

Pro tip: Press the Up arrow key to scroll through your previous commands. Press Down arrow to go forward. Try it!