All community areas on Channel4.com are set to be pre- or post-moderated. One of the moderation team will review your comment before or after it is published, depending on which community area you posted it to. A community area that covers sensitive subject matter is more likely to be moderated before the comments are allowed to go live. Any comment containing something that goes against the Community Guidelines will be removed.
Channel4.com moderators will never contribute to a community area without disclosing their role as a moderator, or as part of C4 Communities, even if they are diligently checking the site while off duty (stranger things have happened... ).
In addition to moderators you may see an 'Editor' or 'Official Contributor'. This could be a Channel 4 member of staff, a freelance programme-maker or someone else connected to Channel 4. Their username will announce their position.