Muslims the world over began to mark the holy month of Ramadan on Sunday.A Malaysian officer uses a telescope to perform "rukyah", the sighting of the new moon of Ramadan, in Putrajaya outside Kuala Lumpur. (photo credit: REUTERS) A woman reads the Koran at her husband's grave in a cemetery, ahead of the Islamic holy fasting month of Ramadan, in Jakarta. (photo credit: REUTERS) A couple reads the Koran at a relative's grave in a cemetery, ahead of the Islamic holy fasting month of Ramadan, in Jakarta. (photo credit: REUTERS) A man prepares traditional sweets ahead of the holy fasting month of Ramadan at the port city of Sidon, southern Lebanon. (photo credit: REUTERS) A man reads the Koran in a mosque in Sanaa, as Muslims prepare for the fasting month of Ramadan. (photo credit: REUTERS) A worker walks past a whirling dervish statue erected as part of decorations ahead of the holy fasting month of Ramadan in the port city of Sidon, southern Lebanon. (photo credit: REUTERS) Filipino Muslim students read the Koran in a classroom next to the Blue Mosque ahead of the holy fasting month of Ramadan in Taguig, Metro Manila. (photo credit: REUTERS) A boy stands amongst Malaysian Muslims who are performing a special prayer ahead of the holy month of Ramadan in Putrajaya, outside Kuala Lumpur. (photo credit: REUTERS) A boy stands amongst Malaysian Muslims who are performing a special prayer ahead of the holy month of Ramadan in Putrajaya, outside Kuala Lumpur. (photo credit: REUTERS) People prepare to break their fast on the first day of the holy month of Ramadan in front of police officers standing guard near Taksim Square in Istanbul. (photo credit: REUTERS) A woman shops for clothing ahead of the upcoming holy fasting month of Ramadan in Medan, North Sumatra. (photo credit: REUTERS) Muslims attend an evening mass prayer session called "tarawih" to mark the holy fasting month of Ramadan at Istiqlal Mosque in Jakarta. (photo credit: REUTERS) Filipino Muslim students hold a prayer before starting to read the Koran during the holy fasting month of Ramadan in Baseco, Tondo city. (photo credit: REUTERS) A boy attends a Friday prayer outside a worship hall of the Niujie Mosque in Beijing, June 27, 2014, ahead of the holy fasting month of Ramadan. (photo credit: REUTERS) Muslims attend an evening mass prayer session to mark the holy fasting month of Ramadan in the Al Akbar Mosque in Indonesia. (photo credit: REUTERS) During Islam's holiest month, observant believers fast from dawn to dusk, and celebrate the end of Ramadan with the Eid al-Fitr festival.Islam is the second-largest religion in the world and observers believe it is the fastest-growing religion.