Storybook is an open-source tool for building and documenting UI components in isolation: a live, browsable catalog of every component and its states, used by both designers and developers to review real, working UI rather than static mockups.
Reviewing components as live, interactive code (not screenshots) means a design review can catch real states (loading, error, empty, hover), that a static Figma frame simply doesn't show.
Genuinely useful for designers working closely with a dev team on a shared design system, not merely a developer-only tool: it's the shared source of truth both sides can point to.
It requires real setup inside a codebase to get value from: it's not a standalone design tool you can use without a development environment already in place.
Open source tool for developing UI components in isolation.
