V-chip
V-chip is a generic term used for a feature of television receivers allowing the blocking of programs based on their ratings category. It is intended for use by parents to manage their children's television viewing. All 13-inch and larger televisions manufactured for the U.S. market since January 1, 2000 are required to have the V-chip technology.
The rated programs' signals are encoded according to the rating, on line 21 of the broadcast signal's vertical blanking interval using the XDS protocol, and this is detected by the television set's V-chip. If the program's rating is outside the level configured as acceptable on that particular television, the program is blocked.
The V-chip technology was developed by Tim Collings of Simon Fraser University.
The V-chip usually does not have password protection or other locking mechanism and is therefore only useful for very young children who cannot change the V-chip settings.
Parodies and spoofs
The V-chip was parodied in the film South Park: Bigger, Longer & Uncut. Template:Spoiler
Eric Cartman, an eight-year-old boy, was constantly swearing as a result of watching the fictional R-rated Terrance and Phillip film Asses of Fire. As a result, a 'V-chip' was implanted in Cartman's brain that delivered an electric shock whenever he swore. The chip later malfunctioned and this helped the heroes defeat Saddam Hussein as he tried to invade the world. South Park is well known for making political statements and social commentary, and presumably the writers were trying to point out that using technology (in this case the V-chip) to forcibly change children's behavior doesn't necessarily improve that behavior or eliminate the perceived underlying cause.