Chinese calendar by mountain peoples. After Qin Shi Huang unified China under the Qin dynasty in 221 BC, the Qin calendar () was introduced. It followed most of the rules governing the Zhuanxu calendar, but the month order was that of the Xia calendar; the year began with month 10 and ended with month 9, analogous to a Gregorian calendar beginning in October and ending in September. The intercalary month, known as the second "Jiǔyuè" (), was placed at the end of the year. The Qin calendar was used into the Han dynasty. Emperor Wu of Han introduced reforms halfway through his
Ramadan (calendar month) religious observances consists of fasting and extra prayers. Some important historical events during this month are generally believed to include: Laylat al-Qadr is observed during one of the last ten days of the month (typically the odd nights). Muslims believe that this night which is also known as "The Night of Power" is better than a thousand months. This is often interpreted as praying throughout this night is rewarded equally with praying for a thousand months (just over 83 years i.e., a lifetime). Many Muslims spend the entire night in prayer. In Islamic eschatology: Ramadan (calendar month) Ramadan (Arabic: )