Using this inside an event handler

Question

I was trying to find the meaning of this keyword inside event handler function in the DOM level 3 event spec.

As per my experiment this ref

Answer 1

In an event handler for an element, with default capturing (false), this will refer to the element which detected the event. Either one may be used.

For example:

element.addEventListener('keydown', function (event) {
    // `this` will point to `element`
}, false);

When capturing an event (true), say at the window level, event.target, will refer to the element which originated the event, while this will refer to the capturing element. For example:

window.addEventListener("error", function (event) {
    event.target.src = 'some_path';
    // `this` will point to window
    // `event.target` will point to the element that had an error
}, true);

I hope this exemplifies the difference between each.