Parental controls are materials required on all TV sets manufactured since 2000 to indicate the refusal of programming deemed by the producer of the block to be "inappropriate" for young children. Parental locks are usually imposed on anything rated PG or higher by the MPAA Rating System, or TV-Y7 or higher by the TV Parental Guidelines. These guidelines require the user to insert a 4-digit password before attempting to view a blocked program (after programming the V-chip). Because of this, there are 10,000 different ways a password might show up.
- Some parental controls are prone to glitches. For example, a block on Time Warner Cable which hides the titles of adult films does not work if you have any other blocks on, causing it to be useless.