Currently, JS framework, as well as a number of development kits and libraries have the following categories, Dojo, Scriptaculous, Prototype, yui-ext, Jquery, Mochikit, mootools, moo.fx
Dojo (JS library and UI component):
Dojo is the most powerful js framework, it give up their own Wiki has a definition, dojo is a JavaScript prepared with open-source DHTML toolkit. dojo would like to make a "unification" of the toolbox, not just the browser level, the ambition is still very large. Dojo including ajax, browser, event, widget, such as cross-browser API, including the expansion of JS language itself, as well as all aspects of the instrument library, and a fairly complete UI component library has also been widely used in many projects, he the characteristics of the UI components are passed to the html tag tag way to increase the expansion, rather than through JS to generate Writing, dojo mimic the API of the Java class libraries organized. Dojo Writing with Web OS is very convenient. dojo is now 4.0 a, dojo is to place a strong interface and effects package, allowing developers to quickly build a number of standards-compliant interface.

Advantages: a comprehensive database, development time is relatively long and powerful, it is said to use dojo's io.bind () can achieve comet, see the vision of its powerful non-general, received the support of IBM and SUN
Disadvantages: relatively large file size, more than 200 KB, the initial download quite slow, in addition, dojo seems to use the class library is not so easy to use, js grammar enhancement than prototype.

Prototype (JS OO library):
Is a very elegant JS libraries, the definition of a JS object-oriented expansion, DOM operation API, and so on case to prototype as the core, forming a peripheral expansion of various JS libraries, are quite promising JS underlying framework, it is recommend, I feel reality is the most widely Class Library (RoR integrated AJAX JS library), above have Scriptaculous components achieve some JS functionality and effectiveness.

Benefits: Basic bottom, easy to learn and use, and even some other js effects of the underlying development kit, size is the smallest.
Disadvantage: If we say that disadvantage is probably the feature are his weaknesses

Scriptaculous (JS UI component based on prototype):
Scriptaculous is based on the prototype.js framework JS effect. Contains six js files, different file corresponds to a different js effects, so that if the underlying use of prototype, then the effect with Scriptaculous to do js that are more suitable for even the famous digg have used him at shows do not generally
Benefits: Based on the prototype are the greatest advantage of using the prototype because of the widespread, users will no doubt book icing on the cake, and "ajax in action" in the case of Scriptaculous effects to tell js
Disadvantage: just the rise, it takes time to hone

yui-ext (JS UI component):
Yahoo UI based on the expansion pack yui-ext is a CS-style Web user interface components to achieve complex Layout layout, interface effects can be comparable BackBase, and the use of pure javascript code development. Real editable table Edit Grid, support for XML and json data types, can move into a direct grid. Lot of components to achieve the support of data sources, such as the layout of dynamic, editable table controls, dynamic loading of the Tree control, dynamic drag effect and so on. Version 1.0 beta start cooperation with jQuery, the jQuery based on Ext 1.0, provides more interesting features.
Advantages: a structured, similar to java structure, clarity, use the bottom of some of the jQuery function, so that integration with the use of selection, the most important point is the interface to allow people to be too shocked.
Disadvantage: too complex, the whole structure of the interface is too complicated.

Jquery:
jQuery is a prototype with the same type of outstanding library js development, especially for the css and XPath support, so that we become more convenient to write js! If you are not a js expert wants to write js excellent effect, jQuery can help you achieve the objective! And brief introduction of the grammar and high efficiency have been the jQuery goal

Advantages: brief introduction and efficiency-oriented, js has the effect of selection of the yui-ext, yui-ext reuse because a lot of jQuery function
Disadvantage: It is said太嫩, history is not long.

Mochikit:
MochiKit claiming to be a lightweight js framework. Python and MochiKit mainly by Python standard library provided by the Department to facilitate a lot of inspiration, in addition to easing the browser inconsistency between versions. In particular, one of the MochiKit.DOM convenient to be able to more than the original JavaScript friendly approach to DOM objects. MochiKit.DOM most of them are customized for XHTML documents, if combining MochiKit and Ajax, using XHTML format in particular, micro-packaged convenience. Mochikit can be directly on the string or the number of formatted output, more practical and easier. It also has its own js code interpreter

Advantages: MochiKit.DOM this part is very useful, brief introduction is also very prominent
Disadvantages: lightweight disadvantage

mootools:
MooTools is a compact, modular, object-oriented JavaScript framework. It can assist you faster and more easy to prepare scalability and compatibility of the JavaScript code. Mootools with prototypejs similar grammar is almost identical. But it provides functionality prototypejs than many, but more powerful. Such as an increase of animation effects, drag and drop and so on.

Advantages: can be customized their required functions, can be said to be an enhanced version of prototypejs.
Disadvantages: medium, specific application of a specific analysis
moo.fx:
moo.fx are a super-lightweight javascript effects library (7k), can with prototype.js or the mootools framework to use. It is very quick, easy-to-use, cross-browser, standards, providing control and modify any CSS property of HTML elements, including color. Its built-checker can prevent users from clicking through on many occasions, or to undermine the effect of madness. moo.fx overall modular design, so it can be developed on the basis of you need any special effects.

Advantages: small size, has great ability to
Disadvantages: so small it has been pretty good