[javascript] Difference between DOMContentLoaded and load events

DOMContentLoaded==window.onDomReady()

Load==window.onLoad()

A page can't be manipulated safely until the document is "ready." jQuery detects this state of readiness for you. Code included inside $(document).ready() will only run once the page Document Object Model (DOM) is ready for JavaScript code to execute. Code included inside $(window).load(function() { ... }) will run once the entire page (images or iframes), not just the DOM, is ready.

See: Using JQuery Core's document-ready documentation.