Fasting during the month of Ramadan is one of the Five Pillars of Islam. The month is spent by Muslims fasting during the daylight hours from dawn to sunset. According to Islam, the Quran was sent down to the lowest heaven during this month, thus being prepared for gradual revelation by Jibreel (Gabriel) to the Islamic prophetMuhammad. Therefore, Muhammad told his followers that the gates of Heaven would be open for the entire month and the gates of Hell (Jahannam) would be closed. The first day of the next month, Shawwal, is spent in celebration and is observed as the "Festival of Breaking Fast" or Eid al-Fitr .
The Islamic calendar is a lunar calendar, and months begin when the first crescent of a new moon is sighted. Since the Islamic lunar calendar year is 10 to 11 days shorter than the solar year and contains no intercalation, Ramadan migrates throughout the seasons. The Islamic day starts after sunset. The actual and estimated start and end dates for Ramadan in 2010–2020 were and are as follows:
Ramadan dates between 2010 and 2020. Dates may vary.
Many Muslims insist on the local physical sighting of the moon to mark the beginning of Ramadan, but others use the calculated time of the new moon or the Saudi Arabian declaration to determine the start of the month. Since the new moon is not in the same state at the same time globally, the beginning and ending dates of Ramadan depend on what lunar sightings are received in each respective location. As a result, Ramadan dates vary in different countries, but usually only by a day. This is due to the cycle of the moon. The moon travels the same path all year round and when the moon is seen in the east, it is then seen traveling towards the west. All the countries around the world see the moon within a 24-hour period once spotted by one country in the east.
Each year, Ramadan begins about eleven days earlier than in the previous year. Astronomical projections that approximate the start of Ramadan are available. 33 Islamic years are approximately equal to 32 tropical years, with six days over.
Ramadan is observed by Muslims during the entire lunar month by the same name. The month of 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.