Claude Code Overview
Claude Code is a command-line tool that gives Claude direct access to your project files and terminal. Instead of copying code back and forth, Claude reads, writes, and runs commands in your actual codebase.
What is Claude Code?
Claude Code is a CLI coding tool from Anthropic. Install it once, run claude from any project folder, and Claude gets full visibility of your files.
Unlike Claude Chat — where you paste code in and paste answers back — Claude Code is wired into your project. It reads existing code, makes changes, and saves files. You review the diff and move on.
Open your terminal, navigate to a project, and run claude. Then describe what you want in plain English.
Claude Chat vs Claude Code
Both use the same Claude model. The difference is what Claude can do during the conversation.
| Claude Chat | Claude Code | |
|---|---|---|
| Access your files | No — you paste code manually | Yes — reads all files in your project |
| Save changes | No — you copy the output yourself | Yes — writes and saves files directly |
| Run commands | No | Yes — npm, pytest, git, and similar |
| Where you use it | Browser (claude.ai) | Terminal, VS Code, or Desktop app |
| Setup needed | None — open the browser | Install once via native installer |
| Best for | Writing, Q&A, quick explanations | Real coding tasks in a real project |
Key capabilities
Claude Code covers the full development workflow — not just writing new code.
Read and write files
Opens, modifies, and saves files across your project.
Understand context
Reads your codebase before acting — no pasting required.
Find and fix bugs
Trace symptoms through multiple files and apply fixes.
Write and run tests
Generate test files, run the suite, iterate until tests pass.
Run terminal commands
Execute npm scripts, git commands, build tools — anything you could type.
Multi-step tasks
Complete a feature end-to-end: files, tests, docs, commit.
Connect external tools
Use MCP to pull in APIs, databases, and third-party services.
Team integrations
Works with GitHub Actions, Slack, and CI/CD pipelines.
What this section covers
The Claude Code module has 26 lessons grouped in five phases:
| Phase | Topics |
|---|---|
| Getting set up | Installation, how it works, permission modes, Desktop app, VS Code |
| Doing real work | Better results, debugging, building apps, writing tests |
| Power features | CLAUDE.md, memory, sub-agents, skills, MCP, hooks |
| Configuration | .claude directory, settings, connecting tools, Chrome extension |
| Integrations | Code review, Git, GitHub Actions, Slack, best practices |
Who it is for
- Developers who want less time on repetitive coding and more on design and problem-solving.
- Students and beginners building real projects who want explanations as Claude works.
- Solo builders who need to move fast without a full team.
- Teams automating code reviews, testing, and CI/CD without custom tooling.
Before you continue
- Claude Code runs in your terminal with direct access to project files and commands.
- Use Chat for questions and writing; use Claude Code when files on disk are involved.
- It reads context, edits files, runs tests, and connects to external tools via MCP.
- This module walks from install through advanced automation in 26 lessons.
- Next: install the CLI and run your first session.
What's Next
Overview done. Next: installing the Claude Code CLI and running your first session takes less than a minute.