(CNN) - For 1.6 billion people, the holiest month of the year began this past Saturday.
The exact starting date sometimes depends on the locale, but most Muslims across the globe will be fasting, praying and abstaining from sex and smoking during daylight hours. Many call it a time of spiritual purity and rededication to God.
Here's everything you need to know about the observance.
What is Ramadan?
Ramadan is the name of the ninth month in the Hijri, or Islamic calendar. The word derives from the Arabic ramida or ar-ramad meaning a fierce, burning heat.
From CNN affiliate KPRC
Houston - New signs posted outside a mosque in Spring Branch, Texas, have sparked outrage from Muslims nationwide.
In black letters, the signs reads, "No Muslim parking in the Westview Shopping Center. Your car will be towed."
The posters lined the street near the El Farouq Mosque, where Muslims heading to worship services said they were were offended.
"I feel sorry for the person who wrote it," Ahmed Hassan told CNN affiliate KPRC. "This is what comes to mind because obviously he has a lot of hate."
From Kiran Khalid CNN
Rye, New York (CNN) –What was meant to be a celebration marking the end of Ramadan turned into a melee at an amusement park on Tuesday when a group of Muslim women were told they weren't allowed on certain rides with their headscarves.
Rye Playland was full of visitors celebrating Eid al-Fitr when the festive mood turned angry. Westchester County Police said the women wearing the hijab, a traditional Muslim headscarf, became argumentative when park employees enforced the no-headgear policy and men sprang to their defense.
By Richard Allen Greene and Yasmeen Amer, CNN
For Christians, the wild celebrations of Mardi Gras come before the solemnity of Lent, a last chance to celebrate before the abstinence marking the 40 days to Good Friday and Easter.
Muslims do it the other way around. First comes the month of daytime fasting during Ramadan, then the eruption of joy called Eid al-Fitr, marked with gift-giving, new clothes, donations to the poor, feasting and festivities.
But as the sighting of a crescent moon officially marked the beginning of Eid on Tuesday, feelings are decidedly mixed for many Muslims.
There's joy tempered with concern on Tahrir Square in Egypt, which saw a successful revolution topple President Hosni Mubarak this year. And there's optimism in Libya, where 42 years of rule by Moammar Gadhafi seem to be coming to an end.
The CNN Belief Blog covers the faith angles of the day's biggest stories, from breaking news to politics to entertainment, fostering a global conversation about the role of religion and belief in readers' lives. It's edited by CNN's Daniel Burke with contributions from Eric Marrapodi and CNN's worldwide news gathering team.