Participating countries at the 2010 World Expo in Shanghai can choose a day as their National Pavilion Day. The day is usually celebrated with ceremonies and performances, which bring the nation's culture and its character to life.

MERRILY MERRILY SING: Artists from Bosnia and Herzegovina sing on stage to celebrate their country's National Pavilion Day on May 9 (FAN JUN)

GREAT IDEA: The original manuscript of Albert Einstein's General Theory of Relativity is on display in the Israel Pavilion to mark its National Pavilion Day on May 6 (LIU DAWEI)

WILDLY JOYFUL: Albanian dancers perform folk dance on their National Pavilion Day on May 5. Albania was the first country to celebrate the day at the Expo (REN YONG)

MUSIC AND DANCE: Artists from Sierra Leone perform on their country's National Pavilion Day at the Expo on May 7 (PEI XIN)

BRUNEI WEDDING: Actors and actresses showcase a traditional wedding ceremony on their country's National Pavilion Day on May 8 (PEI XIN)