What Is Claude Code

Define what agentic coding means and how it differs from autocomplete

Explain what Claude Code can do that other AI coding tools cannot

List three tasks Claude Code can complete autonomously

Recognize situations where Claude Code is the right tool for the job

Identify when a simpler tool might work better

You have probably heard of AI tools that help you write code. GitHub Copilot suggests the next line as you type. ChatGPT answers questions about programming. But Claude Code does something different. It does not just suggest code. It actually writes code, runs commands, and completes tasks on its own.

Think of the difference this way: autocomplete tools are like a helpful passenger reading a map. Claude Code is more like a driver who knows where you want to go, plans the route, and handles the steering while you watch. You stay in control, but you do not have to do everything yourself.

This lesson introduces Claude Code and explains what makes it different from other AI coding tools. By the end, you will understand what "agentic coding" means and know when Claude Code is the right choice for your work.

Most AI coding tools work by suggestion. You type some code, and the tool guesses what comes next. You accept the suggestion or ignore it. The tool waits for you to do something, then guesses again. This is reactive. The AI responds to what you do.

Claude Code works differently. It is agentic, which means it can take action on its own. When you describe what you want, Claude Code does not just suggest code. It reads your files, figures out what needs to change, writes the code, and can even run tests to make sure it works. You describe the goal. Claude Code figures out the steps.

Here is a simple example. Say you want to add a login feature to your website. With an autocomplete tool, you would write code line by line, accepting suggestions as you go. With Claude Code, you could say "add a login page with email and password fields" and watch it create the files, write the code, and connect everything together.

This does not mean Claude Code is always better. Autocomplete tools are great when you know exactly what you want to write and just want to type faster. Claude Code shines when you have a bigger task and want help figuring out how to do it.

Claude Code has capabilities that go far beyond suggesting code. Here are the main things it can do:

Read and understand your entire project. Claude Code looks at all your files, not just the one you have open. It understands how different parts of your code connect. When you ask a question like "how does the login system work?", it can trace the logic across multiple files and explain the whole picture.

Write and edit code across many files. A single change often touches several files. Claude Code can update all of them at once. It shows you what it plans to change and waits for your approval before making edits.

Run commands in your terminal. Claude Code can run your tests, start your development server, install packages, and execute other commands. If a test fails, it can read the error, figure out what went wrong, and try to fix it.

Work with Git. Claude Code can create commits with descriptive messages, make new branches, and even open pull requests. You can say "commit my changes" and Claude Code will stage the files and write a commit message that describes what changed.

Connect to external tools. Through something called MCP (Model Context Protocol), Claude Code can read from databases, check your project management tools, and interact with other services you use.

All of this happens through conversation. You type what you want in plain English, and Claude Code figures out which tools to use and what steps to take.

The AI coding tool landscape has several options. Understanding how they differ helps you pick the right one.

GitHub Copilot is the most widely used AI coding tool. It lives inside your code editor and suggests completions as you type. It is fast, cheap (around $10 per month), and works in almost any editor. But it is reactive. It waits for you to type and then suggests the next bit. It cannot run commands, work across files, or complete multi-step tasks on its own.

Cursor is an AI-powered code editor. It goes further than Copilot by letting you chat with an AI about your code and request changes across files. It has a feature called Composer for multi-file edits. Cursor costs about $20 per month and is popular with developers who want AI deeply integrated into their editing experience.

Claude Code is different from both. It runs in your terminal (or in VS Code, or as a desktop app) and operates as an autonomous agent. It can read your whole codebase, run commands, and work through problems step by step. It costs $20 per month for the Pro plan, with higher tiers available for heavy users.

The key difference is how much the tool does on its own. Copilot suggests. Cursor helps you edit. Claude Code acts. Many developers use more than one tool. They might use Copilot for quick completions while typing and switch to Claude Code for bigger tasks that span multiple files.

Benchmark data supports Claude Code's strength on complex tasks. On SWE-bench Verified, a test that measures how well AI can solve real GitHub issues, Claude Code scores 80.8 percent. That is the highest publicly reported score among available tools as of early 2026.

Claude Code works best for certain kinds of tasks. Knowing when to use it helps you get the most value.

Good fits for Claude Code:

Exploring a new codebase. Ask Claude Code to explain how different parts work, trace execution flows, and find relevant files.

Building features that touch multiple files. Describe what you want and let Claude Code plan the approach.

Debugging tricky problems. Paste an error message and let Claude Code trace the cause through your code.

Tedious tasks you keep putting off. Writing tests, fixing lint errors, updating documentation, resolving merge conflicts.

Git workflows. Creating commits, branches, and pull requests through natural language.

Less ideal for Claude Code:

Quick one-line completions. If you just want the tool to finish your current line, autocomplete is faster.

Real-time pair programming. Claude Code works in turns. It thinks, then acts. It is not designed for rapid back-and-forth while you type.

Offline work. Claude Code requires an internet connection to function.

Free usage. There is no free tier. The minimum cost is $20 per month.

The bottom line: use Claude Code when you have a task that would take you many steps, when you want help understanding code, or when you want to automate routine work. Use simpler tools when you just need a quick suggestion.

Claude Code is an agentic coding tool, meaning it takes action rather than just suggesting code

It can read your entire codebase, write code across multiple files, run terminal commands, and handle Git operations

Claude Code differs from autocomplete tools like Copilot by being proactive rather than reactive

It works best for multi-step tasks, exploring codebases, debugging, and automating tedious work

There is no free tier, so evaluate whether the $20 per month cost fits your workflow

Before you install Claude Code (which we cover in the next lesson), take a few minutes to think about how you currently use AI coding tools.

Write down three tasks from the past week where you wished an AI could do more than suggest code.

For each task, note whether it involved multiple files, running commands, or understanding how different parts of your code connect.

Consider whether Claude Code's agentic approach would have helped with those tasks.

This exercise helps you identify where Claude Code might save you time. Keep this list handy as you work through the rest of this guide. You will learn how to tackle each of these tasks with Claude Code.

https://code.claude.com/docs/en/overview - Official Claude Code overview, capabilities, and installation options

https://github.com/anthropics/claude-code - GitHub repository with 109k stars, feature list, and community

https://www.nxcode.io/resources/news/cursor-vs-claude-code-vs-github-copilot-2026-ultimate-comparison - Comparison of Claude Code vs Cursor vs GitHub Copilot with benchmark data