Young girls hold crescents and stars during street performances celebrating the Muslim holy month of Ramadan, in the southern port city of Sidon, Lebanon, on June 4.  (Mohammed Zaatari/Associated Press)

The Muslim holy month of Ramadan is upon us — starting Monday. Fasting during the day throughout Ramadan is one of the five core obligations of observant Muslims, of whom there are about 3.3 million, according to the Pew Research Center. Many are likely to take part in the fast, which falls during some of the longest, hottest days of the year.

WANT TO KNOW MORE?

Three American imams are here to explain:

The Koran, which Islam teaches is the word of God, came to the prophet Muhammad over the course of his lifetime, but started during the lunar month of Ramadan.

Over the course of the month, Muslims are told to read the entire Koran — or about one-30th each night. And from dawn until dusk, for the 29 or 30 days of the month, to abstain from eating, drinking “and from the feeding of their passions — whether those passions are road rage or romance,” said Johari Abdul-Malik, an imam and the director of outreach at the Dar al-Hijrah Islamic Center in Falls Church, Va. In other words: You’re supposed to be extra good during this holiest of months.

Many Muslim scholars liken fasting to an almost meditative state or a heightened mindfulness that brings one closer to God.

The obligation is laid out in the Koran in the second Surah: “O you who have attained to faith! Fasting is ordained for you as it was ordained for those before you, so that you might remain conscious of God.”

“I have always wished the U.S. Congress would take up fasting during the month of Ramadan,” Abdul-Malik jokes. “Can you imagine Congress being in session and every member of Congress has to tell the truth before God?”

“The word sowm [the Arabic term for fasting] actually means ‘to stop,’ ” says Suhaib Webb, a popular D.C.-based Imam who fields questions about the religion throughout the year, using a range of social media platforms such as Twitter and Instagram.

To Webb, fasting poses an opportunity for broader change. People think, “If I can avoid stuff this month, I can do it the rest of the year,” he said. “You’ll find a lot of people quit smoking in Ramadan.” Others get in shape.

The United Kingdom’s National Health Services devotes an entire webpage to staying healthy during Ramadan. The Islamic Society of North America recently advised its Twitter followers how to be more conscious of environmental protection, too.

“There’s that foundational peace that really creates a tremendous spiritual capacity, really invigorates a person,” Webb says. “It’s a great reminder of what we have the potential to do if we really try.”

WHAT ABOUT THE FOOD?

Let’s be honest: Ramadan also has a reputation as a month of feasting, and there are some people who definitely don’t lose weight.

For many, Ramadan after sundown is just as social as it is religious. Families and friends get together for elaborate iftar meals to break their fasts at sundown. And although iftar often starts with water and dates — which have a low glycemic index, and are therefore less shocking for the body after a long day with an empty stomach — iftar is also a popular time for big dinner parties and extensive cooking. It’s an opportunity for families to showcase “what they consider their national dish,” Abdul-Malik said. (And then there are other nights when iftar is Pizza Hut delivery or McDonald’s after work. After all, it’s a month-long holiday.)

The morning meal, or suhoor, which comes just before dawn — or as the Koran instructs, before “you can discern the white streak of dawn against the blackness of the night” — is a more intimate family affair. Although pre-pubescent children are not required to fast, some enjoy the ritual of getting up while it’s dark to eat with their parents.

FOR BETTER OR WORSE, RAMADAN HAS A DECIDEDLY DIFFERENT FEEL if you’re in a Muslim majority country.

In Egypt, colorful tent fabric appears outside mosques and restaurants, along sidewalks and in alleys, inviting the poor — or anyone — to gather at communal tables for a free meal to break the fast.

Fasting has a tendency to grind bureaucratic functions to halt, and shopping and socializing can turn into nocturnal pastimes.

Zaid Shakir, an Islamic scholar and the co-founder of Zaytuna College, an Islamic college in Berkeley, Calif., spent several Ramadans in Syria in the 1990s, and remembers how the streets of Damascus would go silent just before sundown. “You would not find a single individual on the street. Even the dogs disappeared,” he said. “It was amazing. I think it was indicative of how Ramadan takes over an entire society.”

As members of a minority religion in the United States, Muslims head into their Ramadan fast with the knowledge that most of those around them will not be partaking — and may even be oblivious to the holiday.

But the imams say that can be a good thing. “I enjoy Ramadan in America because America doesn’t stop for it, which is kind of cool because you have to juggle the material and immaterial,” Webb said.

Disciplining yourself to fast in spite of your everyday routines, temptations and responsibilities is part of the point: “When you gotta deal with your road rage, you gotta get kids ready for school, you gotta deal with Islamophobia — and the Muslim community really does feel like it’s under a microscope — it’s kind of a good time to fast.”

NOT EVERYONE HAS TO FAST (AND NOT EVERYONE DOES)

There are plenty of secular Muslims who choose not to fast.

But the Koran also excuses those who are sick or traveling. Generally, that includes women who are pregnant or breastfeeding, people who require daily heart or diabetes medication, children and the elderly; people on airplanes, trains or car rides — or simply out of town.

For those who can’t fast, the Koran says: “God wills that you shall have ease, and does not will you to suffer hardship.” But if they are able, they are expected to make up their missed fasting days later in the year.

RAMADAN IS A TIME WHEN imams get bombarded with questions about where to go to pray (a common query for new immigrants), how best to balance religious obligations with a fast-paced American work life, or family members who don’t fast.

Webb, who answers questions from thousands of young fans over social media, gets queries such as: “Does medical marijuana break my fast?” (Scholarly interpretations differ on whether medication is allowed during fasting. But generally speaking, medical marijuana is a tough call, Webb said.)

A HUGE PART OF RAMADAN is giving to the poor.

According to the Koran, “it is incumbent upon those who can afford it to make sacrifice by feeding a needy person,” and it is said that the prophet Muhammad was the most generous during this month.

And it is common for Muslim charity efforts to go into overdrive during Ramadan. Mosques and wealthy individuals offer free meals to the poor. Nonprofit organizations solicit donations. And the month is a popular time for volunteer work.

Ramadan gives Muslims an opportunity to reflect “upon our responsibilities toward those who are less fortunate than ourselves,” Shakir said.

A WASHINGTONIAN RAMADAN

In recent years, Ramadan in Washington has taken on a bit of the networking political culture that permeates just about everything else, the imams said. The White House hosts an annual iftar, as do a host of Muslim organizations and embassies. Even non-Muslims get in on the action.

“It’s become the thing to do,” Abdul-Malik said. In Washington, you get dressed up, have fancy food “and invite prominent people to dine with you,” he said.

“If the people at the mall only knew that Ramadan is a great time to sell party dresses, they could make a boatload of money,” he added.

IN THE DMV AND LOOKING FOR RAMADAN EVENTS?

DMV.ummahnow.org has a list of other Ramadan events (including a children’s Ramadan camp).

And many area mosques, such as Abdul-Malik’s Dar al-Hijra, will offer free iftar meals to the needy. (Abdul-Malik expects the mosque to feed abaout 1,000 people per night.)

RAMADAN WILL START this year the same way it always does: with the first confirmed sighting of a new moon. Sometimes clouds or smog might get in the way, and experts disagree, so sometimes Ramadan starts on different days in different countries. Scholars and religious leaders tend to make the call.

RAMADAN WILL END with the holiday of Eid al-Fitr, a day of feasting and celebration to mark the end of the fast.

WISH SOMEONE A GOOD RAMADAN WITH: “Ramadan Mubarak,” which means “a blessed Ramadan” or “Ramadan karim” — a “noble” or honorable Ramadan.

Want more stories about faith? Follow Acts of Faith on Twitter or sign up for our newsletter.

Singing ‘salaam,’ synagogue hosts welcome dinner for Syrian refugees

In their 80s and 90s, three women finally become bat mitzvahs

‘All these are qualities we share’: Grand iman on meeting Pope Francis