GitHub Copilot: The Complete Developer Guide for 2026

GitHub Copilot is the reference AI assistant for developers. Launched by GitHub and Microsoft in 2021, it has become a major productivity tool, to the extent that its integration into the daily workflow has become standard across much of the industry.

## What is GitHub Copilot?

GitHub Copilot is a code completion and generation service based on language models. It proposes real-time code suggestions as the developer types, and can also respond to natural language questions through a chat interface.

The tool integrates directly into editors: Visual Studio Code, Visual Studio, JetBrains, Neovim, Xcode, and Eclipse.

## Key Features

- **Code completion**: inline suggestions while typing, accepted by Tab
- **Copilot Chat**: conversational assistant for explaining code, suggesting refactors, generating tests
- **Slash commands**: `/explain`, `/fix`, `/tests`, `/doc` for contextual actions
- **Copilot in the CLI**: terminal command assistance
- **Pull request summaries**: automatic PR description generation on GitHub

## Available Models

Since 2024, GitHub Copilot is no longer tied to OpenAI models exclusively. Users can now choose between GPT models (OpenAI), Claude models (Anthropic), and Gemini models (Google) — allowing cost/quality optimization by task type.

## Privacy and Code Confidentiality

In Business and Enterprise versions, prompts and suggestions are **not used** to train models. An optional filter can block suggestions matching public code, limiting license risks. See our [GDPR checklist](/en/blog/rgpd-outils-ia-checklist-conformite) for the full evaluation framework.

## Our Trust-Vault Assessment

On our [Trust Score methodology](/en/pages/methodology), GitHub Copilot benefits from strong security guarantees (Microsoft SOC 2 Type II) and good transparency. The main consideration is Microsoft vendor lock-in and the need for a clear usage policy for teams handling sensitive code.

For AI developer tool comparisons and verified user reviews, see our [Code Assistant category](/en/categories/code-assistant).