Games as the ultimate form of mental and physical relief are important for adults as they are for children. People learn how to behave, control their emotions, follow the rules. The most obviously essential aspect of this is that people realize that our life is a big game with its own rules. In the next paragraphs I will give the reasons to support my answer.
Basically, there are two types of games. The first type is mental games that help us to upgrade our mental abilities. The second type is the games that involve physical activities. They keep people fit and healthy.
Mental games for adults play a significant role. Adults learn co-operation, discipline, team work, self-confidence. Scientists say that the brain cells of grown up people can grow with the help of mind exercising. The most simple way to exercise one's mind is through mental games. For example, playing chess makes people think, try to predict events, follow the strategy of an opponent.
From the other side, physical games help adults to stay in a good shape, relax, eliminate stress and tension. Also, it is a perfect way to lose weight.
Mental games for children also play an important role. They help children to understand the real world more quickly and adapt to the reality. In addition to those practical benefits mental games teach children how to behave, be supportive and patient. Physical games from the other hand, strengthening children' bones, health and teach discipline.
To sum up, I am sure that people need games and it is not important how old one is.