Many are afraid that
the modern javascript frameworks like jQuery, Prototype,Mootools distort the base javascript language and moves us away from the language foundations.

Actually same applies to any programming language
and its frameworks. For me it is a matter of personal taste. We are free to choose how much we use those frameworks or stay with the language itself.

I don’t choose
my frameworks by how close they stay to the original programming language, but
how fast they help me to reach my project goals. If some people want to philosophy
about it, they are free to do so. A framework summarizing 10 steps into one is a huge benefit when doing complicated or repeating functioanlity.

For me jQuery is the ultimate tool and provides a good set of functioanlity in a rather small sized package. You can easily extend it through its plugin structure. It provides a vivid and balanced community, that also opens its doors for those that are just starting to get their hands dirty, those might just be the innovators of tomorrow.

jQuery UI