javascript.info The Modern JavaScript Tutorial Part 2: 2.2 Bubbling and Capturing by Ilya Kantor
Youtube by Lisa Friedrichsen
This youtube covers the issue of how event handlers fire when multiple elements are clicked on a web page as defined by bubbling versus capturing. The addEventListener() method is used with both bubbling (the default) versus capturing to demonstrate both ways of firing multiple event handlers that are triggered at the same time on a web page. Bubbling versus capturing is fundamental to event delegation, applying one event handler to the ancestors of many child elements, which is the concept of the next lesson (Part 2, 2.3 Event Delegation).

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