Some components need to generate a unique id for each instance. This could serve as suffixes to element ID's for example. useInstanceId provides a unique instanceId to serve this purpose.
/**
* WordPress dependencies
*/
import { useInstanceId } from '@wordpress/compose';
function MyCustomElement() {
const instanceId = useInstanceId( MyCustomElement );
return <div id={ `my-custom-element-${ instanceId }` }>content</div>;
}