Answer :
Darkening a screen so that you can type without seeing what is being written is known as a privacy screen.
This technique is commonly used when working on sensitive information in public spaces to prevent others from viewing the screen content.It can also be achieved by hitting the "B" key on a PowerPoint or using a lamp without shade or flashlight with a barrier to block the screen's visibility.Changing the direction or orientation of text or using a dark room with a small hole for projection are other methods to achieve visual privacy.
