The festival is held on the last day of the sixth Tibetan month. In Tibetan language Shoton means yogurt. Before the end of the 16th century, it was purely religious. In light of the monastic discipline at that time, monks stayed in retreat for dozens of days, during which they were forbidden to go out to avoid killing any insects. Afterwards, the lay people would donate yogurts to them. That was the Origin of the festival. Later on in the middle 17th century, the Tibetan opera play was gradually added as a major event, and therefore, it is also known as Tibetan Opera Festival. Since then it has been celebrated regularly, but still outside of monasteries. Until the early 18th century, the Norbulinka was inaugurated as the summer palace of the Dalai Lama, and also as the official venue of the annual Festival, where ordinary people were allowed access to watch the opera playing. A set of ritualized programs was thus formed. The troupes from different regions are gathered in Lhasa to perform Tibetan Opera and some epic picnics in Norbulinka. Yogurt is also a must on the day. Meanwhile, people in Lhasa would adorn themselves with festive attire, and bring with them a lot of food to enjoy the day in Norbulinka. And Buddha paintings are exhibited at this time, it is also called “Tibetan Opera Festival” or “Buddha Exhibition Festival”. Hundreds of thousands of Tibetans, tourists go to Drepung Monetary and Sera Monastery to see the famous Giant Buddha Thangka.