What does it mean to flag something?

Registered users are given the ability to flag any submitted content on the website. This can be done by pressing the "flag" link associated with the content item. Content should be flagged when the article or link is offensive, unrelated, or spam. When content is flagged, administrators are notified and will either revise or delete the content if necessary, as soon as possible. Flagging content helps keep the site full of only useful content.