[Requirement] Use standards scripting languages [Details] Use the DOM API combined with Ecmascript (but don't make the use of scripts mandatory to navigate in the site!). [Test tool] N/A [Rationale] 
DOM and Ecmascript (the common standard behind Javascript and JScript) are the best way to go to get interoperable scripts to create animations in your Web site. But do not forget your users that don't have these scripting capacities enabled.