Green Screen Backgrounds are dyed materials that are dyed before even being woven. This seems to stop them from fading. They are seamless, machine washable, and ready to use.
Green screens are most commonly used in local weather reports on TV. No, they aren't changing the maps on the wall. They are merging the background in with the green screen.
Green screens are sometimes used in movies to give some of those spectacular special effects. The digital background can easily be changed. Bruce Willis used green screens in a lot of his movies in order to get some of the special effects that made his movies so popular. Green screen backgrounds were used in the Superman movies and with The Greatest American Hero TV show.
Instead of having to hang a new backdrop every time, the green screens allow a digital background to be merged with the screen, giving a more varied visual effect. A lot of photographers are using green screens along with digital pictures to make their work more unusual and pleasing to the eye. Children's picture with a green screen might be merged with a background of A-B-C blocks and then changed to a background with toys all around them using the same picture of the children with the green screen. The parents might have their picture taken with a beautiful lake in the background. Then the teenagers might have a park setting as their background. The green screen is what allows for all this variety.