It is a name of a website. I just found this excellent site for programmers few days ago. The purpose is same as many other sites having forums to discuss programming questions. But this one is not based on forums, rather on question/answer style discussions. To differentiate between the languages/tools/areas tags are used. Answers as well as questions can be voted up or down. But not anyone has the right to vote. The right comes with reputation which can be earned by being active. Badges can be earned based on many criteria. Overall, I liked the innovations the site brings. And which matters most is people are active and make the site useful. The site is run by Fog Creek Software.