Yahoo! recommends YUI 3. Learn about YUI 3 on YUILibrary.com.
In this example, the use of several key Dom Collection methods is explored. Given the markup in the source section, you can invoke any of the methods by clicking on them; the Source is updated, as is its in-browser appearance (Render). In the Outupt section, you can review the elements that are selected or affected (or, in a few cases, the JavaScript return value) of the function you invoked.
You can load the necessary JavaScript and CSS for this example from Yahoo's servers. Click here to load the YUI Dependency Configurator with all of this example's dependencies preconfigured.
Note: Logging and debugging is currently turned off for this example.
All YUI 2.x users should review the YUI 2.8.2 security bulletin, which discusses a vulnerability present in YUI 2.4.0-2.8.1.

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