Muslims around the world will begin observing Ramadan Saturday.

Ramadan is the ninth month of the Islamic lunar calendar and the holiest time of the year for Muslims.

Irfan Sheikh of the Islamic Center of Tucson said the Quran prescribes a month of fasting during this time.

“It is taken as a training session in everybody’s life once a year," Sheikh said. "For one month everybody is on a diet program you could call it – it’s a spiritual diet as well as a physical diet program in which we sustain from eating and drinking anything from sunrise to sunset every day.”

Sheikh pointed out that the first Ramadan fast occurred during the hottest time of the year – but the lunar calendar is ten days shorter than the solar calendar.

“So every year, our holidays fall ten days earlier. So for example 20 years ago Ramadan was actually in December," he said.

Sheikh said when Ramadan occurs during the long days of summer, it’s much more challenging, at least at first.

“But when you know everyone around you is fasting, it becomes very easy after a couple of days," he said.

Community is a very important element of the month, and Tucson’s mosques host events every night during Ramadan where hundreds of people come together to break fast and to recite one-thirtieth of the Quran each night, completing the entire book by the time the month of Ramadan comes to an end.