Lesson 1: Your Terminal Is Not Scary
Fast-track: Already comfortable with the terminal? Know how to open it, run commands, and navigate folders? Skip to Lesson 2.
What is a terminal?
A terminal is a text-based way to talk to your computer. Instead of clicking icons, you type commands. That's it. It looks intimidating at first, but you'll only need a handful of commands to build real software.
Open your terminal
On Mac: Press Cmd + Space, type "Terminal", and hit Enter.
On Windows: Press Win + X, then click "Terminal" (Windows 11) or "Windows PowerShell" (Windows 10). Either one works for this course.
You should see a window with a blinking cursor. That's your terminal. You're in.
felipeabello@macbook-pro ~ %
Your terminal will show something like felipeabello@macbook-pro ~ % before the cursor. This is just your terminal telling you it's ready — you don't need to type this part. Here's what each piece means:
felipeabello— your computer's username@macbook-pro— your machine's name (yours will look different)~— the folder you're currently in (~means your home folder)%— means the terminal is ready for input (you might see$instead — same thing)
In this course, our code examples show a clean $ before each command for readability. Your terminal will look different — that's normal. Just type the command after the % or $.
A few survival commands
You don't need to memorize a hundred terminal commands — and if you forget something, you can always come back to this cheat sheet or just ask Claude Code. Your terminal is always "inside" a folder, just like a file explorer window. When you open it, you start in your home folder. Here are the commands to look around and move between folders:
| Command | What it means | What it does |
|---|---|---|
↑ ↓ arrow keys | — | Scroll through your command history. Press ↑ to reuse the last command |
Tab | — | Autocomplete file and folder names. Type cd my- then press Tab |
cd folder-name | Change Directory | Move into a folder. cd my-project |
cd .. | Change Directory (up) | Move up one folder. Go from my-project/ back to its parent |
ls | List | List files in the current folder. Just type ls and hit Enter |
mkdir folder-name | Make Directory | Create a new folder. mkdir my-project |
Two tricks that'll save you a lot of typing:
- Arrow keys — press
↑to reuse your last command instead of typing it again. - Tab to autocomplete — start typing a file or folder name, then press
Taband the terminal fills in the rest. If there are multiple matches, pressTabtwice to see the options. You'll never have to type out a long folder name again — type the first few letters and let Tab do the work.
Checkpoint
You're ready for the next lesson if:
- You can open a terminal window
- You know what
%or$means in your terminal (it's ready for input) - You know a few basic commands (
cd,ls,mkdir) - You know that closing and reopening the terminal refreshes installed programs