modular JavaScript toolkit - Dijit

 Dojo Toolkit is an open source modular JavaScript library
 designed to ease the rapid development of cross platform,
 JavaScript/Ajax based applications and web sites.
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 This package contains the Dijit widget system.
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 Dijit provides a complete collection of user interface controls based
 on Dojo, giving you the power to create web applications that are
 highly optimized for usability, performance, internationalization,
 accessibility, but above all deliver an incredible user experience.