Visual Studio Code, usually shortened to VS Code, is a free source-code editor from Microsoft that runs on Windows, macOS, and Linux. Microsoft announced it during the opening keynote of its Build 2015 developer conference on April 29, 2015, describing it as “a free, lightweight, cross-platform code editor for Mac OS X, Linux, and Windows.” The move was notable because the Visual Studio brand had until then been a Windows-only family of tools; VS Code carried the name onto every major desktop platform.
The editor is a desktop application built on Electron, which embeds the Chromium rendering engine and the Node.js runtime so that the interface can be written with web technologies while still running as a native app. Its text-editing core is the Monaco editor, the same component Microsoft had developed for browser-based editing. The bulk of the codebase is written in TypeScript; the public GitHub repository reports the project as over 95 percent TypeScript. The early effort was led by Erich Gamma, one of the authors of the “Design Patterns” book and a designer of the Eclipse Java tooling, working from Microsoft’s development center in Zurich.
Microsoft open-sourced the editor’s source as the “Code - OSS” repository under the MIT license, while the branded product that most people download is “a distribution of the Code - OSS repository with Microsoft specific customizations (including source code), released under a traditional Microsoft product license,” as the project’s FAQ explains. That split lets Microsoft ship proprietary additions such as branding and certain integrations on top of an otherwise open foundation, with the proprietary pieces making up only a small fraction of the overall code.
VS Code’s reach came largely from its extension model and from its early adoption of the Language Server Protocol, a Microsoft-originated convention that lets a single language analysis server provide completion, navigation, and diagnostics to any compatible editor. Rather than building deep language knowledge into the editor itself, VS Code lets language servers and extensions supply it, which made it practical to support a long tail of programming languages without bloating the core. The repository now lists hundreds of monthly releases, reflecting the project’s steady cadence of updates.
Within a few years of launch, VS Code became the most commonly used development environment in large industry developer surveys, displacing both heavier full IDEs and older lightweight editors. Its combination of a fast editing core, a large extension marketplace, and free availability across platforms made it a default choice for a generation of developers and a reference example of a desktop app built on web technology.