Install it, sign in, and have it do its first real job for you. Mac and Windows, side by side. About twenty minutes.
Claude Code is Claude running on your own computer, in your own folders. You type what you want in plain English. It reads your files, writes new ones, runs commands, searches the web, and asks before it changes anything. Programmers use it to write software. I use it for that too, and also to run my websites, read my email, build spreadsheets and cut videos. The chat window you already know is Claude with its hands tied.
There are two ways in and they share the same brain, settings and memory. You can start with one and switch later.
A text window where you type claude and talk to it. It looks intimidating for about four minutes. This is how I learned it and it is the version everything else is built on.
The Claude app you may already have has a Code tab. Same engine, with a sidebar for several sessions, a visual diff view and a browser preview. If the terminal puts you off, download the app, sign in, click Code, pick a folder, and skip to step 07.
This is the door I came in through. My first session was the Code tab, in a folder, before I had ever opened a terminal. The first thing it asked me to do was install Git.
Terminal and press Return.% or $. That is where you type.PowerShell and press Enter. No need to run as administrator.PS C:\Users\you>. If there is no PS, you opened Command Prompt instead. Close it and open PowerShell.Paste into a terminal with Cmd + V on a Mac and a right click or Ctrl + V in PowerShell. Nothing happens until you press Enter.
One line each. Paste it, press Enter, and wait. The installer shows no progress bar while it downloads, so a quiet minute is normal.
curl -fsSL https://claude.ai/install.sh | bash
If you already use Homebrew, brew install --cask claude-code does the same job, but you update it yourself with brew upgrade claude-code.
irm https://claude.ai/install.ps1 | iex
Also install Git for Windows with its default options. Claude Code uses it to run commands the way it does on a Mac. Without it everything still works, through PowerShell, with a few features missing.
Or, if you prefer the Windows package manager: winget install Anthropic.ClaudeCode.
The one line installer keeps itself up to date in the background. You will never have to install it again.
Close the terminal window and open a new one. Then type:
claude --version
You should see a version number followed by (Claude Code). If the terminal says the command is not found, the new window usually fixes it. If not, step 10 has the next thing to try.
For a fuller health check that also catches settings problems:
claude doctor
Claude Code works inside a folder, so first move the terminal into the one you want help with. Then start it.
cd ~/Documents/my-project claude
Tip: type cd with a space, then drag the folder from Finder into the terminal window. It fills in the path for you.
cd $HOME\Documents\my-project claude
Tip: in File Explorer, open the folder, click the address bar, copy the path, and paste it after cd .
You only sign in once. Type /login later if you ever need to switch accounts.
Talk to it the way you would brief a sharp colleague who has just sat down at your desk. Try these in order. Click one to copy it.
Two habits that change the results more than anything else. Be specific: "fix the login bug where users see a blank screen after a wrong password" beats "fix the bug". And let it look first: "read through the project and tell me how it works" before "change it".
By default it asks before it edits a file or runs a command. You see what it wants to do and press y or n. You can say yes for the rest of the session to a kind of action, or you can press Shift + Tab to cycle through the permission modes, from asking about everything to planning only. Start in the default mode and loosen it once you trust what you are seeing.
Press Esc to stop it mid task. It stops and waits for you.
| In the terminal | Does |
|---|---|
claude | Start a new session in this folder |
claude -c | Continue the last conversation here |
claude -r | Pick an older conversation to resume |
claude "fix the build" | Start with a task already typed |
claude update | Update now instead of waiting |
| Inside a session | Does |
|---|---|
/help | List everything available |
/init | Write a CLAUDE.md file: standing notes it reads every time |
/clear | Wipe the conversation, keep the folder |
/resume | Reopen a past conversation |
/exit | Leave. Ctrl + D twice also works |
Type / on its own and it lists the commands and skills you have. Tab completes them. The up arrow brings back what you typed before.
| You see | What it means | Do this |
|---|---|---|
claude: command not found or not recognized | The new program is not on your path yet | Close every terminal window and open a fresh one. If it persists, run the install line again, then claude doctor. |
The token '&&' is not a valid statement separator | You pasted the Command Prompt line into PowerShell | Use the PowerShell line from step 04. |
'irm' is not recognized | You pasted the PowerShell line into Command Prompt | Open PowerShell and paste it there. |
| Sign in loops or a 403 error | The account has no Claude Code access | Check the plan is Pro, Max, Team or Enterprise, then /login again. |
| It keeps asking permission for every tiny thing | You are in the strictest mode | Shift + Tab to the next mode, or answer "yes, and don't ask again for this". |
Anything else: ask it. "Why did that fail?" works on its own errors too. The full guide is at code.claude.com/docs.
None of this needed me to write code. I described the job, checked what it proposed, and said go.
Next episode: the one file that makes it remember how you like things done.