There sure are a lot of Q&A sites on the Internet, but not all Q&A sites are the same. In the Founder Stories video above, Stack Exchange CEO Joel Spolsky talks about the origins of Q&A sites and his competition. Stack Exchange operates Stack Overflow and other peer-reviewed knowledge sites. Spolsky minces no words in his contempt for the Big Daddy of Q&A sites, Yahoo Answers . "Yahoo Answers is Teenage chat," says Spolsky. "Nobody wants to find Yahoo Answers in their search results. It is one-sentence gibberish." Stack Overflow, in contrast, goes deep . Stack Overflow users gain reputation by giving the best answers, and answers are peer-reviewed. It doesn't cover every topic under the sun, either, just programming.