The title should be prefixed with "Ask HN: " The reason HN does not need a captcha is that it has 2 full time moderators that watch this site continuously. Th

The title should be prefixed with "Ask HN: " The reason HN does not need a captcha is that it has 2 full time moderators that watch this site continuously. They do an incredible job at weeding out abusive content. There is some automation that also helps them flag the obvious abuse and people can also flag submissions to help that system. If you enable "show dead" in your profile, you will see some of the content that gets removed.