Scriptaculous
// January 6th, 2006 // Technology Bits
Matt recently came across and got very excited about Script.aculo.us for doing DHTML effects and AJAX.
From Matt’s post: Script.aculo.us Is My New Best Friend:
Script.aculo.us is a Javascript Effects and Control framework developed by Thomas Fuchs, a software architect living in Vienna, Austria who, like me, was disappointed by current web application frameworks that made no sense to him. His framework is 3 things: Easy to Use, Simple, and Easy to Use. His libraries – built off of the AJAX framework, Prototype – blow SAJAX out of the water!
One of the things that makes script.aculo.us especially great is the detailed and well written documentation/apis. Arguably, this is why I first loved Java and eventually became addicted to PHP. The Java API was great, but PHP.net is unmatched. Like PHP.net, the script.aculo.us wiki allows users to contribute back knowledge easily.
2012 
[...] As we’ve begun adopting Ajax, JSON, and similar JavaScript heavy technologies a problem quickly arose. Suddenly our clean HTML was being cluttered with tons of script tags, onclicks, and other various event handling functions. Trying to extract this logic back out of the HTML was a definite desire for us. [...]