"By using the Discovery Sites, you agree not to post or transmit any defamatory, abusive, obscene, threatening or illegal material, or any other material that infringes on the ability of others to enjoy the Discovery Sites or that infringes on the rights of others."

Also:

"Although Discovery.com cannot monitor all the posts in the chat rooms, forums and other public areas, we reserve the right (but assume no obligation) to delete, move or edit any postings that come to our attention that we consider unacceptable or inappropriate, whether for legal or other reasons."