Preact is a 3kB alternative to React with the same modern API — components, hooks, and JSX — plus first-class fine-grained reactivity through `@preact/signals`. Use when a user wants to build a performance-critical web app, embedded widget, or mobile-first site with a smaller bundle than React, wants to add reactive signals state, or wants to reuse an existing React component library on top of Preact via the `preact/compat` layer.
