Another Douglas Crockford video. This time Douglas talks about the Document Object Model, about how Java failed, and JavaScript evolved thanks to DHTML and DOM. He talks about how to use DOM to traversing and manipulating elements in an HTML document, walking the DOM, making elements, innerHTML, as well as Events, memory leaks. He talks about the cracks in DOM, and how we must be prepared to back off when we hit the browser limits of DOM.
A useful overview / introduction of the jQuery library, covering using selectors and XPath expressions to target specific elements in a document, simple Ajax requests, the basic animations available, restructuring a document, creating jQuery plugins.