Welcome to brain Stuff from how Stuff Works dot com where smart Happens. I am Marshall Brain with today's question, what does a V chip really do and how does it work? As of all new television sets sold in the United States have to contain a V chip. The V stands for viewer control and the goal of the chip is to allow parents to choose the level of TV programming that will be allowed into the home. The
idea behind a V chip is simple. TV shows have a signal embedded into them that gives the show a rating, and the chip can detect these ratings. The ratings that the FCC has settled on look like this. T V Y is for all children. All children can watch because it has zero violence and zero sexual content. TV Y seven for all children seven and over. T V G is for general audiences. There's no sex, violence, or inappropriate language. TV PG is parental guidance suggested. TV fourteen is suitable
only for people over fourteen. There's some sex and violence. And then t V M A is suitable only for mature audiences and it can contain just about anything. A parent can program the TV with a rating and the TV will block all shows above that rating. So if apparent programs in the TV Y seven rating, the TV will allow only shows rated at TV Y or t V y seven, but it will block all other shows. How does your TV see the rating of a show? The ratings are encoded in what's called the line twenty
one data area. All sorts of things go inside this data area, such as closed captioning information and the time of day, as well as the ratings information. It's basically hidden in a part of the TV signal that doesn't show up on the screen. The V chips simply decodes the line twenty one data uh, compares it with the parents allowed rating that they've programmed into the chip, and then either blocks the signal or lets it through. Do
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