Many of the world's one billion Muslims have spent the last several days preparing for the month of Ramadan, the ninth and holiest month in the Islamic calendar.
Across much of the world, Ramadan begins tonight (Aug. 10) with the sighting of the new moon. For the next 30 days, believers will abstain from eating, drinking, smoking and having sex from dawn to dusk.
For Muslims, Ramadan marks the month during which God, through the angel Gibril (Gabriel), revealed the Qur'an to the Prophet Muhammad.
The beginning of Ramadan has already been observed Indonesia and much of the Middle East and will occur in North America tonight.
See PHOTOS of the preparations and initial observances below: