Event Bubbling and Delegation: Core JavaScript Concepts Worth Mastering

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A frontend developer returning to JavaScript after a year away used the experience to revisit core concepts rather than relying solely on AI-generated code. Reviewing a 2024 accordion FAQ project revealed an inefficient pattern of attaching individual event listeners to every button on the page. The developer explains how event bubbling — where a click event travels up through parent elements — enables a cleaner approach called event delegation. With delegation, a single listener on a parent element handles all child clicks, using event.target and the closest() method to identify exactly which element was interacted with. The article is the first in a planned series aimed at helping developers build a deeper understanding of how and why JavaScript works the way it does.

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