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Claude Code Quickstart

Install a terminal coding agent, authenticate, point it at a real project, and ship your first committed change in about ten minutes.

Codingbeginner4 min readUpdated 12 Jun 2026

In short

  1. 01Claude Code is a coding agent in your terminal that reads and edits your project and asks before changing anything.
  2. 02Install it with a one-line command, sign in once with a subscription or API account, and point it at a real project.
  3. 03Work in a rhythm: you ask in plain English, it reads what it needs, and you approve each edit before it lands.
  4. 04Add a memory file with init so Claude knows your conventions, then make and commit your first change in about ten minutes.
Contents · 6 sections
  1. 1How do I install Claude Code?
  2. 2How do I sign in to Claude Code?
  3. 3The loop: ask, review, approve
  4. 4What is a CLAUDE.md file?
  5. 5Which slash commands should I know first?
  6. 6Your first ten minutes

Claude Code is a coding agentA program that can read and change your code on its own, taking multiple steps to finish a task you describe that lives in your terminal. You talk to it in plain English, it reads and edits the files in your project, and it asks before it changes anything. This guide gets you from nothing installed to your first committed change.

The whole loop in about twenty seconds: ask, review, approve, commit. Illustrative session.

How do I install Claude Code?

On macOS, Linux, or WSLWindows Subsystem for Linux, a feature that lets you run a Linux environment directly inside Windows, run the one-line installer:

curl -fsSL https://claude.ai/install.sh | bash

That is it. Claude Code ships as a single standalone CLICommand-line interface, a tool you run by typing commands into a terminal instead of clicking a graphical app from Anthropic, so there is nothing else to set up.

How do I sign in to Claude Code?

Move into a project you already have with cdChange directory: a terminal command that moves you into a different folder, then launch the agent:

cd path/to/your-project

Run claude to start Claude Code. The first run asks you to authenticate.Common gotchaStart claude from inside the project folder, not your home directory, or it has no code to work on.Make sure that folder is a git repo too, so every edit is something you can review and undo.

Sign in with a Claude subscription (Pro, Max, Team, or Enterprise), a Console account with API credits, or a company cloud like Amazon Bedrock or Google Vertex AI.

Your login is stored locally, so you only do this once.

The loop: ask, review, approve

Working with Claude Code is a three-step rhythm.

  1. You ask for something in plain language. No need to name files.

    what does this project do?

  2. It reads whatever it needs · your folder structure, the relevant files, recent gitGit is the version-control system that tracks every change to your code over time; a git history is the full log of those changes history · and answers or proposes an edit.

  3. It asks permission before touching anything. You see the exact change before it lands, and you approve or reject it.

That permission step is the safety rail. If you want fewer prompts once you trust it, press Shift+Tab to cycle through permission modes, from ask-every-time to accept-edits automatically.Common gotchaIt is tempting to jump straight to accept-edits to stop the prompts. On a codebase you do not know yet, stay on ask-every-time for the first few changes.Once you have seen the kind of edits Claude proposes, then slide along the scale.

Most oversightFewest prompts
  1. Ask every time
  2. Accept edits
  3. Auto-run
  4. Bypass all checks
Shift+Tab cycles the safe modes. The far end, run with --dangerously-skip-permissions, turns every check off: only ever inside a throwaway sandbox, never on your real machine.

What is a CLAUDE.md file?

CLAUDE.md is a markdownA plain-text format that uses simple symbols like # and * to add headings, bold, and lists, and renders as formatted text on most platforms file in your repoA repository: the folder that holds your project and all its git history that Claude Code reads at the start of every session. It is where you write the things you would otherwise repeat every time: build commands, coding style, where things live, the rules that matter.

Get a starter without writing it by hand · run /init and it drafts one from your codebase. CommitA commit saves a named snapshot of your changes into git history so you and your team can revisit or undo them the file and your whole team gets the same conventions for free. Keep it tight · under about 200 lines · so the guidance stays sharp. There is a whole guide on rules and memory files when you want to go deeper.

Which slash commands should I know first?

Type / to see everything Claude Code offers. You will reach for these first:

  • help · list commands and docs
  • memory · create or update your project's CLAUDE.md
  • clear · wipe the conversation and start fresh
  • model · switch which model is answering
  • plan · a read-only mode that proposes a plan before editing (covered in the next guide)
  • login · re-authenticate or switch accounts

Your first ten minutes

A realistic warm-up on a project you already have:

  1. cdChange directory: a terminal command that moves you into a different folder into the project and run claude.
  2. Ask "what does this project do?" and let it map the codebase.
  3. Ask follow-ups: "where is the entry point?", "what does the build command do?"
  4. Make a small change: "add a hello world function to the main file." Review the proposed edit and approve it.
  5. Check your work: "what files have I changed?"
  6. CommitA commit saves a named snapshot of your changes into git history so you and your team can revisit or undo them: "commit my changes with a clear message."

Ten minutes in, you have made and committed a change without opening a single file yourself. That is the whole idea: you stay in charge of what and why, and hand off the mechanical how.

Once this feels natural, the next guide turns it into a real workflow · plan mode, memory, subagents, and code review.