What is batching in React?

Batching in React is a mechanism that combines multiple state or prop updates into a single render. Instead of re-rendering the component after each setState call, React groups several changes and performs one unified render, which improves performance.

For example, if you call multiple setState functions in a row inside an event handler, React will apply all changes in one pass rather than multiple times. In React 18, batching has started to work not only within React events but also in asynchronous callbacks, which has enhanced update efficiency.