The Terminal & Claude Code

The Terminal: A Text-Based Finder

Every computer has a terminal. On Mac it is called Terminal, on Windows it is Command Prompt or PowerShell. It looks like a black box with a blinking cursor. And it does the exact same thing as Finder or File Explorer. It lets you navigate folders, open files, move things around. Just text instead of pictures.

Here are the four commands that cover 80% of what you will ever do:

• ls lists what is in the current folder (like opening a Finder window)
• cd folder-name moves into a folder (like double-clicking it)
• cd .. goes back up one level (like clicking the back arrow)
• pwd prints where you are right now (like looking at the path bar in Finder)

Four commands. That is all you need to navigate your file system.

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File Paths: Every File Has an Address

Every file on your computer has an address called a path. It works like a street address, telling you exactly where something is by listing every folder you would pass through to get there.

/Users/you/Documents/my-project/index.html

Read it left to right: start at the root (/), go into Users, then you, then Documents, then my-project, and there is your file index.html. Each / is a folder boundary.

URLs work the same way. When you visit https://example.com/blog/post-1, everything after the domain is a path: /blog/post-1. The server looks inside its blog folder for something called post-1. Same concept, different computer.

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IDEs: Your Workshop

An IDE (Integrated Development Environment) is where developers actually work. The two most popular ones are VS Code (free, from Microsoft) and Cursor (a fork of VS Code with AI built in). They look almost identical.

An IDE combines three things you already know into one window:

1. A file browser (the left sidebar). It is Finder. Same folders, same files. You click to open them.
2. A text editor (the main area). It is where you read and write code. Think of it as a very fancy Notepad with color-coding.
3. A terminal (the bottom panel). It is the exact same terminal from the previous section, just embedded in the window.

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The #1 Confusion: What Am I Looking At?

This is the hardest part of this entire curriculum. Learners consistently get confused about which tool they are in. Let's name the confusion so it loses its power.

You are going to have three things open that all look similar:

1. The Mac Terminal app, a standalone black window with a blinking cursor. You type commands here.
2. VS Code, a code editor with a file browser on the left, code in the middle, and a terminal panel at the bottom.
3. Claude Code, an AI that runs INSIDE a terminal. It looks like a terminal. It is inside your terminal.

Here is the key: Claude Code is a terminal inside your terminal. When you launch Claude Code, the terminal you were using transforms. It still looks like a terminal (black background, text, blinking cursor) but now you are talking to an AI instead of talking to your computer's operating system.

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Claude Code: AI in the Terminal

Claude Code is an AI that runs in the terminal. Not in a chat window, not in a sidebar. In the same terminal you just learned about. You type a description of what you want, and Claude Code reads your files, writes code, runs commands, and commits changes. It is operating directly on your project.

This is different from AI assistants built into editors like Cursor. The distinction matters:

• Cursor AI is like having an assistant look over your shoulder while you type. It suggests the next line, autocompletes, answers questions in a sidebar. You are still driving.
• Claude Code is like handing the keyboard to the assistant. You describe what you want, and it does the work. It reads files, makes edits across multiple files, runs the build to check for errors, fixes what breaks, and commits the result.

Both are useful. They are just different modes. Cursor is great when you want to stay hands-on. Claude Code is great when you want to describe a task and let AI handle the execution.

"Why not just use the terminal directly?" Because the terminal only understands specific commands. You have to know the exact syntax. Claude Code lets you describe what you want in plain English, and it figures out which commands to run, which files to edit, and in what order. It is the difference between driving a car yourself and telling a driver where you want to go.

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Escape vs. Ctrl+C: Two Ways to Stop

When working in the terminal and Claude Code, you need to know two different "stop" commands:

• Escape cancels the current input or interrupts what Claude is doing. It is the "nevermind" button inside Claude Code.
• Ctrl+C kills whatever process is running in the regular terminal. If a command is stuck or taking too long, Ctrl+C stops it.

The distinction: Escape is for Claude Code. Ctrl+C is for the terminal. If you press Ctrl+C inside Claude Code, it may exit Claude Code entirely and drop you back to the regular terminal. If that happens, just type claude to start it again.

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Setting Up Your Environment

Getting set up is simpler than you would expect:

1. Install VS Code (or Cursor). Download it, drag it to Applications, done.
2. Open a folder. File > Open Folder. Pick your project. The file browser on the left now shows everything in that project.
3. Open the terminal. View > Terminal (or press Ctrl+`). A terminal panel appears at the bottom. You are ready.

That is the full setup. You now have a file browser, a text editor, and a terminal, all in one window. From here you can navigate files, read code, run commands, and (once installed) use Claude Code.

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Why This Matters

Every tool in this curriculum builds on what is in this lesson. You cannot use Claude Code without a terminal. You cannot navigate a codebase without understanding file paths. You cannot work on a project without an IDE (or at least a text editor and a terminal side by side).

These are the physical tools. The keyboard, the workbench, the workshop. Everything else (code, repos, APIs, databases, cloud hosting) happens inside these tools. If the terminal and IDE feel comfortable, everything that follows will make more sense.

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Further Reading