Apple Updates Safari 5
www.apple.com/safari/?sr=hotnews.rss
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
Apple today released Safari 5.0.1 and introduced the Safari Extensions Gallery. Extensions allow users to quickly add powerful new features to Safari — from toolbars that display live web feeds to sophisticated programs that filter web content. Users can download and install extensions either from the Safari Extensions Gallery or directly from a developer’s site.