Install, sign in, and look around

01The goal

By the end of this lesson Claude Code is installed and signed in, you have started a session inside a real repository, asked it two questions about the code, and can name the version, model and account the session is running on.

02The idea

Claude Code is a program you run in a terminal, inside a project folder. It reads the files around it and answers questions about them; in later lessons it changes them. Nothing mystical — your folder is its world, and the terminal is where you talk.

Before you trust anything a session tells you, know three things about it. The version, because features and defaults move between releases. The model, because models differ in what they can do. The account, because it decides which features and models you get. The header at the top of the session shows the version and the model; the /status command shows all three together, with the login method and the email. It is the same instinct as checking which branch you are on before you commit: ten seconds that prevent an hour of confusion.

03The walkthrough

1. 01Install on macOS, Linux or WSL: curl -fsSL https://claude.ai/install.sh | bash — then open a new terminal. On native Windows, in PowerShell: irm https://claude.ai/install.ps1 | iex.
2. 02Check it: claude --version prints a version followed by "(Claude Code)". If the shell cannot find the command, the install folder is not on your PATH yet — the installation-troubleshooting page fixes this in a minute.
3. 03cd into a repository you own — a scratch repo is ideal; every lesson from here on assumes you can make a mess and clean it up — and run claude.
4. 04First run asks you to sign in. Choose your account type at the terminal prompt; with a subscription or Console account you finish in the browser. If the browser shows a code instead of sending you back, paste it into the terminal.
5. 05The workspace-trust dialog appears the first time in a repository you have not trusted: it asks whether you trust the folder, and "No, exit" is the highlighted default. Trust is a decision, not a formality. You made this repo, so arrow down to "Yes, I trust this folder". Trust is remembered per repository — and never granted to a folder whose contents you do not know.
6. 06Read the header above the prompt: version, model, folder. Then type /status and find the same three, plus Login method and Email. Esc closes it.
7. 07Ask two questions: "what does this project do?", then one only the code can answer — "which file parses the config, and how do I run the tests?". Claude reads files to answer; your wording will differ, the shape will not.
8. 08End the session with /exit.

A note on versions: this course was verified against the stable channel. Claude Code follows the latest release unless you choose otherwise, so your version may be newer than ours — when something behaves differently, the official pages cited in each lesson are the tiebreaker.

04Your turn

In your scratch repository, save the version output to a file by running claude --version > version.txt. Start a session, note the model and account information from the /status command, ask two questions of your choice, and then exit with /exit. If the repository is new to you, execute git status afterward — asking a question can prompt Claude to run a command that modifies the repository, such as running tests. A new session can edit most files and execute most commands without prior confirmation; the next lesson will cover this functionality.