Jotai is an atomic state management library for React that stores state as small, composable atoms — individual pieces of state that components subscribe to directly, re-rendering only when that specific atom changes. As the creator of CoreUI with 25 years of front-end development experience, I use Jotai when an application needs fine-grained reactive state updates with minimal overhead and no external state management infrastructure. Jotai atoms are simpler than Redux slices and more granular than Zustand stores, making them ideal for UI state like filter values, modal open/close, or selected items in a list. The API is intentionally minimal — just atom() and useAtom().