Hide and seek. Hide and seek is a popular game of children. I don't know what about in other countries, but in my country, especially in the countryside where I'm living, no one doesn't know this game and almost people have memorizable moment with this folk game in their childhood. The rule seems to be very simple that players who conceal themselves in surrounding environment in a certain time will be found by one or more seekers. Players who can conceal without being found out and can touch to a certain place will become winners. This rule may be different between other regions. In this game, children can fully relax without facing with smartphone, computer or other devices. Moreover, intelligence, wiseness and flexibility are very essential in this game. So, it is a interesting and meaningful game for children.