Msg#: 4029381 posted 8:22 pm on Dec 4, 2009 (gmt 0)
I'd call prototype a *predecessor* to all the other JS frameworks, like Mootools, JQuery, and Dojo. It was (one of) the first, easily the best, and quickly gained popularity because of Scriptaculous, a suite of animation effects that used the Prototype framework.
If you already use JQuery, prototype will not be a challenge to learn.
Prototype offered a new release just this past September with a host of improved features. The inclusion of mixins and inheritance shows that it's evolving further in the same direction as Mootools; both are maturing as solid object-oriented frameworks.