http://www.prototypejs.org/download Prototype1.6官方下载
全福编程网下载地址
Learn about what's new in version 1.6.
Prototype SVN
If you want the full development package (including unit tests), you can use Subversion to checkout the source code:
svn co http://svn.rubyonrails.org/rails/spinoffs/prototype/trunk prototype
Build the distribution with rake dist
and find more details about this in the contribution guide.