Monday marked the first calendar day of Ramadan 2013, the holy month for Muslims around the world, who will fast and practice abstinence from dawn until sunset for 30 days. The annual event marks the anniversary of the Quran being revealed to the Prophet Muhammad.

Ramadan is held during the ninth month of the 12-month Islamic calendar, starting after the sighting of the new moon. The holy month lasts for 29 or 30 days, this year beginning on Monday, July 8, at sunset, or “rukyah,” when the moon is spotted, and going on until the next new moon appears, on Wednesday, Aug. 7. The month of fasting is celebrated by more than 1.5 billion Muslims around the world, including in the U.S., where there are nearly 2.6 million Muslims, according to the Pew Research Center.

This year, one of Britain’s top broadcasters, Channel 4, will broadcast the three-minute call to prayer at 3 a.m. on each day of Ramadan. The channel's act of “deliberate provocation” is designed to break the stigma for those who associate Islam with terrorism. While it has caused a bit of controversy for British citizens, assistant secretary-general of the Muslim Council of Britain Ibrahim Mogra told Voice of America that the move will make Muslims feel welcome in British society. “I think this will certainly help,” he said. “It is not going to dispel all the myths and misconceptions about Islam in one go. But every effort helps.”

The purpose of Ramadan is to focus on spirituality, praying more often and withholding any acts of violence during the fast. All Muslims around the world are expected to participate, with the exception of the elderly, sick and pregnant, by wishing each other "Ramadan Kareem" or "Ramadan Mubarak."

As one of the five pillars of Islam, Muslims are expected to refrain from food and drink and abstain from smoking and sex each day during the celebration from dawn to dusk. The breaking of the fast, or iftar, begins at dusk by eating dates. Some Muslims have slightly different variations and have broader definitions of practices during Ramadan.

Ramadan commences annually with a celebration called Eid al-Fitr, comprised of feasting and prayer. Ramadan ends with the three-day Eid al-Fitr festival, sometimes abbreviated as Eid, where many feast and join in Islamic prayer, known as salat, while saying "Allahu Akbar" or "God is Great.”

Ramadan 2013
A vendor displays dates at a market in Sanaa, as Muslims prepare for the fasting month of Ramadan, the holiest month in the Islamic calendar, July 7, 2013. Reuters
Ramadan 2013 in Taguig, Philippines
Filipino Muslim students pray at the IBN Khaldon Asian Integrated Institute in Maharlika village, Taguig city, south of Manila July 9, 2013. Philippines' President Benigno Aquino on Tuesday called for unity and cooperation among Filipino Muslims as they prepare to start the observance of the holy month of Ramadan. Ramadan is the most sacred month of the Islamic calendar. During this month, Muslims fast and offer prayers from dawn until sunset. The Philippines will be starting Ramadan on Wednesday, local media reported. Reuters
Ramadan 2013 in Kabul, Afghanistan
A fruit vendor awaits customers ahead of the Islamic holy month of Ramadan in Kabul, July 8, 2013. Muslims around the world abstain from eating, drinking and conducting sexual relations from sunrise to sunset during Ramadan, the holiest month in the Islamic calendar. Reuters
Ramadan 2013 in Bandar Seri Bebawan, Brunei
Brunei's Islamic religious officers perform "rukyah", the sighting of the new moon of Ramadan, in Bandar Seri Bebawan July 8, 2013. Muslims scan the sky at dusk in the beginning of the lunar calendar's ninth month in search of the new moon to proclaim the start of Ramadan, Islam's holiest month, during which observant believers fast from dawn to dusk. Reuters
Ramadan 2013 in Putrajaya, Malaysia
A Malaysian Islamic religious officer performs "rukyah", the sighting of the new moon of Ramadan, in Putrajaya outside Kuala Lumpur July 8, 2013. Reuters
Ramadan 2013 in Old City, Israel
A Palestinian man hangs decorations at the entrance to the compound of The Dome of the Rock in Jerusalem's Old City July 8, 2013, ahead of the upcoming holy month of Ramadan. Reuters
Ramadan 2013 in Baghdad, Iraq
A vendor sells at his shop ahead of the fasting month of Ramadan at the Shorja wholesale market in central Baghdad, July 9, 2013. Ramadan is the ninth and holiest month in the Islamic calendar, during which Muslims around the world abstain from eating, drinking and conducting sexual relations from sunrise to sunset. Reuters
Ramadan 2013 in Mogadishu, Somalia
A vendor displays bananas at his stall in Somalia capital Mogadishu as Muslims prepare for the fasting month of Ramadan, the holiest month in the Islamic calendar, July 8 2013. Reuters
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