The world is full of screens. They are on TVs, computers and smartphones. Screens are at school, at home, and just about everywhere in between. The time people spend every day looking at screens is known as "screen time. " Most families have rules about how much time children can spend with screens. Why do they have rules? Are there good reasons to limit screen time?
In many ways, screens are helpful for communication and connecting with other people. Social media and video calls allow people to be always in touch with one another. ____ By sharing and commenting on videos, photos, games or music, people can meet others who have similar interests.
However, some adults are worried that young people spend too much time on screens and not enough time meeting people in real life. As a result, they may not properly understand feelings or develop strong relationships. Many kinds of screen time may be good for students. Students may use screen time to develop their skills in creating music or videos. They may even learn skills such as coding（编程）computer programs. When students use their screen time to do research online, they may meet people who are different from them or ideas they have never thought about before.
However, some researchers think that screens change how the brain processes information. Some have linked （连接） screen time to lower test scores or less attention time.
In the future, scientists will continue studying the effects of screen time. Parents will likely continue to make rules limiting screen time. Plenty of good things can come from all this screen time, but it's a good idea for people to pay attention to how much time in a day they spend looking at a screen. They should know how screen time influences their health, relationships, and learning.
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