Usually you will often see videos taken using a green screen to change the background. This effect can save film making costs. The screen used is not always green, it can also be blue or blue screen depending on conditions and needs.
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Why does it have to be a green screen?
The goal is to isolate the background color from the color of the object in front of the screen. Green is often called the best color because it is a contrasting color and usually no part of the human body is green. What if the object is green? Usually uses a blue screen, and vice versa. What about other colors like red, yellow, orange or white? Actually, it is possible that the color of your object does not contain that color because during the process of removing the background, it is possible that some of your objects will also disappear because they are carried away by the background color.