A billion Muslims around the world are celebrating Ramadan.
The month-long observance—which likely begins the evening of March 22 in 2023—sees Muslims fasting from dawn to sunset, reciting verses from the Quran and attending prayer sessions. For many of those observing Ramadan, it is a time to become closer to God. It is also a time of joy and for spending time with one’s family, and giving to charity and those in need.
Here’s what you need to know about Ramadan, which is considered the holiest month in Islam.
When is Ramadan?
Ramadan begins during the ninth month of the Islamic lunar calendar when the new crescent moon is first sighted. The exact start date of Ramadan is confirmed when the moon is spotted by a sighting committee, often made up of government officials and religious scholars.
The first day of fasting in 2023 is likely to be March 23.
The end of Ramadan is marked with the sighting of the crescent moon, marking Eid-al-Fitr, which will be in mid-April.
What is Ramadan and how is it observed?
Ramadan is observed by Muslims to commemorate when God revealed the first chapters of the Quran, Islam’s sacred text, to the Prophet Muhammad. Muslims believe that during this period, the gates of heaven are open and the gates of hell are closed.
Muslims mark the holy month by fasting—considered to be one of the five pillars of Islam—during sunlight hours. The pre-dawn meal is called the suhoor, while the fast is broken at dusk with the iftar, traditionally starting with a few sips of water and some dates.
During Ramadan, offices and schools in many Islamic countries shut early.
How do you wish someone a Happy Ramadan?
You can exchange Ramadan greetings by saying “Ramadan Kareem,” which in Arabic translates into “Have a generous Ramadan,” or “Ramadan Mubarak,” which roughly translates into “Happy Ramadan.”
On the last day of Ramadan, which is Eid-al-fitr, the greeting changes to “Eid Mubarak.”
Various Muslim-majority nations in Africa, Asia, and elsewhere use other greetings in their native languages.
Does everyone have to fast?
Not everyone must fast. Islam prescribes that all able-bodied Muslims should fast during Ramadan but exempts young children, expecting and breast-feeding mothers, women who are menstruating, the elderly, and those with health conditions.
Non-Muslims visiting an Islamic nation are not expected to fast, but they are expected to refrain from eating and drinking in public spaces to respect those around them.
How long is Ramadan fasting?
The length of daily fasts during Ramadan depends on where you live and when the sun rises and sets. It can be as short as 12 hours in southern countries like New Zealand or as long as 18 hours, in places like Iceland.
Some Islamic scholars have proposed a more lenient fast for those in countries with extraordinarily long fasting times; that includes observing their fast according to Saudi Arabia’s time or the time of the nearest country that does not have near continuous daylight.
Ramadan starts about 10 to 12 days earlier each year because it is tied to the Islamic calendar, which relies on a lunar calendar in which months are 29 or 30 days long.
What is not allowed during Ramadan?
Abstinence during Ramadan isn’t just restricted to food and water, though. It extends to refraining from sexual activity, smoking, and even to jealousy, anger, or other negative thoughts. Muslims believe that following these practices during Ramadan will lead to self-purification, self-control and bring them closer to God.
— WITH REPORTING FROM SANYA MANSOOR / NEW YORK
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Write to Kamakshi Ayyar at kamakshi.ayyar@time.com