<p>Ask Ubuntu is run by Stack Exchange, Inc. (which also run Stack Overflow and <a href="http://stackexchange.com/sites">about 90 other sites</a>. The software itself is closed source, but there are plenty of <a href="http://meta.stackexchange.com/questions/2267/stack-overflow-clones">alternatives</a> that strive to achieve the same effect of Stack Exchange platform.</p>