Terminal & Command Line — CodeSensei Teaching Module

The Terminal

• Analogy: The terminal is like texting your computer. Instead of clicking buttons, you type instructions and it responds. It's not scarier than that.
• Key insight: Everything you can do by clicking in a graphical interface, you can do faster by typing in the terminal. Developers prefer typing because it's faster and scriptable.

Essential Commands

Teach these as they appear in the user's session:

Navigation

• cd [folder] — "Change Directory" — walk into a folder
• ls — "List" — see what's in the current folder
• pwd — "Print Working Directory" — "where am I right now?"
• Analogy: You're in a building. cd is walking to a room, ls is looking around, pwd is checking the room number on the door.

File Operations

• mkdir [name] — "Make Directory" — create a new folder
• touch [file] — create a new empty file
• cp — copy, mv — move/rename, rm — delete
• ⚠️ Teach: rm is permanent. There's no trash can.

npm (Node Package Manager)

• Analogy: An app store for code. Other developers built tools and shared them. npm install downloads those tools into your project.
• npm install [package] — download and add a tool
• npm run [script] — run a pre-defined task (like "start the server" or "run tests")
• package.json — the shopping list of all tools your project uses
• node_modules/ — the warehouse where downloaded tools live (never edit this!)

git (Version Control)

• Analogy: A time machine for your code. Every "commit" is a save point you can go back to.
• git add — stage changes (put items on the "to save" pile)
• git commit — save a snapshot with a description
• git push — upload your snapshots to the cloud (GitHub)
• git pull — download the latest from the cloud
• Key insight: Git exists because code breaks. It lets you undo mistakes by going back to when things worked.

Environment Variables

• Analogy: Secret notes that your app can read but aren't written in the code itself. Like a password you whisper instead of writing on a whiteboard.
• .env file — where secrets live (API keys, database passwords)
• ⚠️ Teach: NEVER commit .env files to git. That's like posting your passwords publicly.

Scary-Looking but Simple

• | (pipe) — sends output from one command as input to another, like a conveyor belt
• > — saves output to a file instead of showing it on screen
• && — "do this AND THEN do that" (run two commands in sequence)
• sudo — "do this as administrator" (the master key)