fluentui

Fluent UI Web is a Microsoft open-source project that provides a collection of utilities, React components, and Web Components for building web applications. The repository hosts three separate projects that can be combined, allowing gradual migration between versions. The three projects are: - React Components (v9): described as new, future-proof and forward looking, used by Microsoft 365. Distributed on npm as @fluentui/react-components, with documentation at react.fluentui.dev. - React (v8): described as mature, used by Office. Distributed as @fluentui/react, with documentation at aka.ms/fluentui-react. The README notes v8 is still widely used and encourages migration to v9, pointing to a migration overview and component mapping guide. - Web Components: a Web Component implementation of Fluent UI, used by Edge. Distributed as @fluentui/web-components. Each project has its own README, changelog, quick start guide, documentation site, and issue labels within the shared repository. The README states that combining Fluent UI React v9 components with v8 or v0 components is possible and supports gradual migration. The project also references Fluent UI Insights, a video series covering design and decisions behind the design system, with episodes on positioning, styling, Griffel, foundational APIs, theming, and accessibility by default. Licensing: all files in the repository are subject to the MIT license, while usage of referenced fonts and icons is subject to a separate assets license agreement. The project has adopted the Microsoft Open Source Code of Conduct. Historical notes: the former Office UI Fabric React project evolved into Fluent UI, and the office-ui-fabric-react repository became this fluentui repository; the library formerly known as office-ui-fabric-react is now available as @fluentui/react. Fluent UI React Northstar was superseded by Fluent UI React Components v9 and reached end of life in July 2025.