A girl displays a “smile card” during an event marking World Smile Day in a kindergarten in Yantai City, East China’s Shandong Province, yesterday. World Smile Day is celebrated on May 8. Established by the World Mental Health Organization in 1948, it is a global festival that celebrates the universal human expression of smiling. The smiley face, created by commercial artist Harvey Ball in 1963, has become a globally recognized symbol of goodwill and cheer.Xinhua | 