jQuery: Difference between "return false" and "event.preventDefault()"

In JavaScript jQuery code, some seem to use a "return false" and an "event.preventDefault()" interchangeably. But what is the exact difference between these two lines of code?

An Example

First, we want to have a look at an example with "return false":

$("a").click(function() {
    return false;
});

And here is an example with event.preventDefault():

$("a").click(function(event) {
    event.preventDefault();
});

Both examples make sure that the actual action (clicking on an a-element is calling the appropriate link) is suppressed. But what is the difference?

The Difference

The difference is that a "return false" has further reaching consequences than a preventDefault(). A preventDefault() merely provides that the default action is not executed, a return false in jQuery, however also ensures that a stopPropagation() is executed. This means that a performed action such as a click on an element is not given further to the underlying elements.

Therefore, the code:

function() {
    return false;
}

Is the same as:

function(event) {
    event.preventDefault();
    event.stopPropagation();
}

However, only in jQuery! Within JavaScript in normal non-jQuery event handlers "return false" does not have this effect, and also after a "return false" the action is passed there anyway.