Google has shut down the human curated web directory named Google Directory last week, on July 20th.
The web directory - which was hosted at http://directory.google.com - was organized into 16 broad categories and further subcategories, and was based on DMOZ, an open-source project also known as the Open Directory Project (ODP).
During the early days of the World Wide Web, web directories were a preferred way to discover and find content on the web but with the advent of crawler-based search engines, the relevance of web directories have diminished. Below is a screenshot (for remembrance) as the page was on July 17, 2011 - also archived here.
The rival project Yahoo! Directory is, however, still up and running at http://dir.yahoo.com/.
Update 2014-12-31: Yahoo! has also shut down its web directory which I have logged here.