What is the difference between controlled and uncontrolled components in React?

Direct answer

A controlled value is driven by React props or state, while an uncontrolled value keeps important state internally, often in the DOM for native form inputs.

Feature	Controlled	Uncontrolled
Current value	Supplied by React state/props	Managed internally or by the DOM
Typical text input	value + onChange	defaultValue or no value prop
Coordination	Easy for parent logic to control	Less configuration
Source of truth	React state/parent	Element or component's local state

The terms also apply more broadly to component design: a component is more controlled when important behavior is driven by props from its parent.