Preact is a lightweight JavaScript library that provides React-like functionality for building user interfaces with a virtual DOM, but in just 3kb instead of React's larger footprint. Developers use it when they want React's component model and API familiarity without the size overhead, making it ideal for performance-critical applications or resource-constrained environments. It handles DOM diffing and updates efficiently while maintaining compatibility with much of the React ecosystem.

preactjs, developit, marvinhagemeister, drewigg, jdecroock, rschristian