Terminal & PowerShell Basics for This Text

Why this guide exists

Many people have never used the terminal (Mac) or PowerShell (Windows) before.
That is completely normal.

This short guide teaches only what you need to successfully complete the setup and run Python code later. It is not a complete rundown of this interface.

You do not need to memorize commands or understand how your computer works internally.
You just need to be comfortable running a small number of commands and recognizing when something worked.

What the terminal / PowerShell is (plain language)

Think of the terminal as:

A text-based way to tell your computer exactly what to do, step by step.

Instead of clicking buttons, you:
- type a command
- press Enter
- read the result

The terminal:
- works inside a folder
- runs commands in order
- shows errors immediately when something goes wrong

What this guide assumes (and teaches)

By the end of this guide, you should be able to:

  • open Terminal (Mac) or PowerShell (Windows)
  • type or paste a command
  • run a command
  • know whether it worked
  • know which folder you are in
  • move into a different folder

Part A — Opening the terminal

macOS: Open Terminal

You have two common options:

Option 2: Applications folder

  • Applications → Utilities → Terminal

Windows: Open PowerShell

Option 2: Right-click menu (sometimes available)

  • Right-click in a folder
  • Choose Open in Terminal or Open PowerShell here

Part B — What you see when it opens

When the terminal opens, you will see:
- a block of text
- a blinking cursor

Example (Mac):

username@computer-name ~ %

Example (Windows):

PS C:\Users\username>

This line is called the prompt.
It tells you:
- who you are
- which computer you are on
- which folder you are currently in

The most important rule

Important

Commands run in the current folder.
If you are in the wrong folder, commands will fail or create files in the wrong place.

Part C — Running commands

How to run a command

  1. Click in the terminal window
  2. Type (or paste) a command
  3. Press Enter

Example:

python --version

The computer will respond immediately.

Copying and pasting commands

  • Mac: Cmd + C (copy), Cmd + V (paste)
  • Windows: Ctrl + C (copy), Ctrl + V (paste)
Tip

It is perfectly fine to copy and paste commands, it is not the way everyone learns, but it can be a great way to just get started. But becomew an expert like this. Just a solid user.

How to tell if a command worked

A command usually worked if:
- no error message appears
- you see output (text) that looks reasonable
- the prompt returns and waits for the next command

Example of success:

Python 3.13.1

How to tell if a command failed

A command likely failed if: - you see words like error, not found, or command not recognized
- the output looks red or alarming
- nothing happened and the prompt did not return

Example of failure:

python : The term 'python' is not recognized

When this happens:
- stop
- read the message
- do not keep running commands blindly

Part D — Where am I? (folders)

Check your current folder

Mac

pwd

Windows

cd

This prints the folder you are currently in.

List files in the current folder

Mac

ls

Windows

dir

You should recognize file names you expect to see.

Part E — Moving between folders

Change folders (cd)

cd means change directory.

Example (Mac)

cd Documents

Example (Windows)

cd Documents

Move into a specific folder

cd CLASS_FOLDER

(Replace CLASS_FOLDER with the actual folder name.)

Move up one level

cd ..

This is useful if you accidentally went into the wrong folder.

Warning

Folder names must match exactly, including capitalization.
If a folder name has spaces, it is harder to use in the terminal.

Part F — Stopping a command

If a command appears to be stuck or running too long:

  • Press Ctrl + C

This safely stops the command.

Part G — Common beginner mistakes (and fixes)

“Nothing happened”

  • Did you press Enter?
  • Is the cursor still blinking?

“Command not found”

  • You may have typed the command incorrectly
  • You may not have the software installed yet
  • Check spelling carefully

“Permission denied” (Mac/Linux)

  • This usually means you are trying to modify a protected folder
  • Move your project into Documents or your home folder

I’m nervous I’ll break something

Important

You are very unlikely to damage your computer by running commands in this guide.

We do not:
- delete system files
- modify protected locations
- require administrator access

Final confidence check

Before moving on to the setup guide, make sure you can:

  • open Terminal or PowerShell
  • run a command
  • see output
  • move into a folder
  • stop a command with Ctrl + C

If you can do those things, you are ready.