When handling events in JavaScript, you often need to control how an event behaves after it is triggered. Three important methods of the event object—stopPropagation, stopImmediatePropagation, and preventDefault—allow you to manage the flow and default actions of events.

Use stopPropagation when you want to prevent an event from bubbling up to parent elements. For example, if you have a button inside a form and you only want the button's click event to be handled, calling stopPropagation on the event will stop it from reaching the form's event listener.

The stopImmediatePropagation method not only stops the event from bubbling up, but also prevents any other event listeners of the same type on the same element from being called. This is useful if you want to ensure that no other event handlers are executed after your handler runs.

The preventDefault method is used to stop the browser's default action for an event. For instance, clicking a link (<a>) normally navigates to a new page. If you want to handle the click in JavaScript and keep the user on the same page, you can call preventDefault to block the navigation.

These methods give you fine-grained control over how events are handled and how they interact with the DOM and browser behaviors.