Microsoft's autocomplete that started the AI-coding category; by 2026 expanded to Workspaces, Chat, and CLI but still the gentlest on-ramp for new AI-coding adopters.
From Wikipedia
GitHub Copilot is a code completion and programming AI-assistant developed by GitHub and OpenAI that assists users of Visual Studio Code, Visual Studio, Neovim, Eclipse and JetBrains integrated development environments (IDEs) by autocompleting code. Currently available by subscription to individual developers and to businesses, the generative artificial intelligence software was first announced by GitHub on 29 June 2021. Users can choose the large language model used for generation.