Jquery sees sets of HTML nodes as objects to pass messages to (more like the traditional Ruby way). So instead of having a separate class that adds text after an HTML node, jQuery glues the functionality onto the jQuery object, which is returned by the $ function. By contrast, Prototype’s $ function returns a vanilla DOM node. In Prototype effects you can inherit your effect from some base effect and this have some nice features like configurable 'easing' function, which can control effect speed over time, or some other stuff for free.