What are the differences between neung, won and myo?

• Royal tombs are classified, according to the status of the buried person, into three different Korean terms: neung, won and myo. Neung refers to the tomb of a king or a queen, and won refers to that of the parents of a king, a crown prince or a crown princess. The tomb of other members of the royal family is called myo, which is the same as that of ordinary people.
• The tombs of Prince Yeonsan and Prince Gwanghae, both of whom were demoted from king to prince, are called Yeonsangunmyo and Gwanghaegunmyo, respectively. On the other hand, the tombs of Crown Prince Uigyeong and Prince Jeongwon, who were given the posthumous titles of King Deokjong and King Wonjong respectively, were promoted to Jangneung and Gyeongneung.