What can GitHub Copilot do?
GitHub Copilot can autocomplete code as you type, answer coding questions in chat, write unit tests, explain and refactor code, fix bugs, generate documentation and commit messages, and — in agent mode — plan and make multi-file changes autonomously. It works across dozens of languages in editors like VS Code, plus on GitHub.com and the command line.
Why — the first-principles explanation
Everything Copilot can do flows from one ability: turning context plus a request into code or text. Because coding work is mostly reading, writing, and transforming structured text, that single capability fans out into a surprising range of tasks.
The first family is writing. Copilot completes lines and whole functions as you type, converts plain-English comments into code, scaffolds files, and generates boilerplate across dozens of languages. This is where it saves the most raw typing time.
The second family is understanding and transforming existing code. Through chat, it can explain an unfamiliar function, refactor messy code, translate between languages, generate unit tests, and propose bug fixes. Because it reads your open files, its answers are grounded in your actual project rather than generic examples. It also drafts the connective tissue around code: documentation, commit messages, and pull-request summaries.
The third family is doing multi-step tasks via agent mode. Instead of a single suggestion, you give a goal — 'add a search feature' — and Copilot plans the steps, edits several files, runs terminal commands and tests, and iterates toward a working result, checking in for approval. This is the biggest leap: from finishing your sentence to completing your assignment.
The boundary is consistent across all three: Copilot proposes, and it can be confidently wrong. It's excellent at common patterns and drafts, and it needs a human to verify correctness, security, and fit. Think capable assistant, not infallible authority.
An example that makes it click
Imagine a Swiss Army knife for coding. One tool finishes your sentences (autocomplete). Another answers your questions (chat). Another writes the little tests that check your work. Another translates a note in English into working instructions. And the biggest blade tackles a whole chore start to finish (agent mode) — like assembling a bookshelf while you supervise.
All those blades fold into one handle: describe what you want, and Copilot produces text or code for it. You still inspect each result before trusting it, the same way you'd check that the bookshelf is actually screwed together tightly.
Key facts
- Copilot autocompletes code and converts plain-English comments into working code across dozens of languages.
- Via chat it explains code, refactors, translates between languages, and generates unit tests and bug fixes.
- It drafts documentation, commit messages, and pull-request summaries.
- Agent mode plans and executes multi-file changes, running commands and tests toward a stated goal.
- It runs in VS Code, Visual Studio, JetBrains, Neovim, and Xcode, plus GitHub.com, mobile, and the CLI.
The AI pair-programmer built into your editor.
Affiliate link — we may earn a commission at no cost to you.▶ The 60-second explainer (script)
What can GitHub Copilot actually do? A lot more than autocomplete — though it does that too. Let's group it into three families. First, writing code. Copilot finishes your lines and whole functions as you type, turns plain-English comments into code, and scaffolds boilerplate across dozens of languages. That's where it saves the most typing. Second, understanding and changing existing code. Through chat, it can explain a confusing function, refactor messy code, translate between programming languages, write unit tests, and suggest bug fixes — all grounded in your actual open files. It'll even draft your documentation, commit messages, and pull-request summaries. Third, and the biggest leap: agent mode. Instead of one suggestion, you give it a whole goal, like 'add a search feature.' Copilot plans the steps, edits multiple files, runs commands and tests, and iterates until it works — checking in with you for approval. So it goes from finishing your sentence to completing your assignment. One constant across all of it: Copilot proposes, and it can be confidently wrong. It's brilliant at common patterns, but you're the one who verifies correctness and security before shipping.
What authoritative sources say
People also ask
Can Copilot write tests?
Yes. In chat you can ask it to generate unit tests for a function or file, and it drafts them grounded in your actual code.
Can it explain code I don't understand?
Yes. Highlight code and ask Copilot Chat to explain it; it walks through what the code does in plain language.
Can it make changes across many files?
In agent mode, yes. You describe a goal and Copilot plans steps, edits multiple files, runs commands, and iterates toward a working result.
What languages does it support?
Dozens, including popular ones like Python, JavaScript, TypeScript, Java, C#, Go, and more, with stronger performance on widely used languages.