Eid al-Adha, also known as the "Sacrifice Feast", is a festival celebrated every year by the Muslim community all over the world. In the Islamic lunar calendar, Eid al-Adha falls on the tenth day of Dhu al-Hijjah. It lasts for 4 days until the thirteenth day. In the international calendar, the date varies from year to year drifting approximately 11 days earlier each year. Eid al-Adha honors the willingness of Ibrahim to sacrifice his son. He did this as an act of submission to God's order, before God arbitrated by sending his angel Jibra'il to notify him that his sacrifice had already been accepted. The meat from the sacrificed animal is divided into 3 parts. One third of the share is retained by the family, one part is given to relatives, friends and neighbours; and the remaining is given to the needy.Similar to Eid al-Fitr, the Eid al-Adha also starts with a Sunnah prayer of two rakats which is followed by a sermon. The celebrations start after the descent of the Hujjaj. The sacrifice may last until the sunset on the thirteenth day of Dhu al-Hijjah. The prayers of Eid al-Adha are offered at the mosque. The prayer of Eid al-Adha is performed any time after the sunrise to just before the entering of Zuhr time. Along with the sunnah of Muhammad, Muslims prepare themselves for the eve of Eid. Muslims are recommended to do certain things in preparation for the Eid al-Adha festival, including; make wudu (ablution) and offer Salat al-Fajr, prepare for personal cleanliness, dress up nicely, put on new or best clothes available.The festival is referred to as "Bakr-Eid" in Urdu and Hindustani languages stemming from al-Baqara, an Arabic word that means "The Cow". Some have wrongly ascribed it to the Hindustani and Urdu word bakr?, meaning "goat", because of the custom of sacrificing a goat on this festival. People dress up in their finest clothing to perform the prayers of Eid al-Adha in a large number in an open field of Eidgah or mosque. Wealthy Muslims who can afford to sacrifice their best domestic animals as a symbol of Abraham's readiness to sacrifice his only son. The animals are called a??iya, also known by the Perso-Arabic term qurb?ni, needs to meet certain standards else the animal is considered an unacceptable sacrifice. During this day, millions of animals are slaughtered all over the world. The regular charitable practices of the Muslim community are observed during Eid al-Adha. No impoverished person is left without an opportunity to participate in the sacrificial meal. In Saudi Arabia, Hajj is performed before Eid ul Adha. A large number of Muslims perform Hajj. During Hajj, millions of Muslims slaughter animals and divide the meat into three parts. During Eid al-Adha eve, the takbir is enchanted out loud before the Eid prayers on the first day and after prayers throughout the four days of Eid. Takbir is considered important during the Islamic festival of Eid al-Adha. In some countries, families do not own domestic animals. In that case, families make a contribution to a charity that will provide meat to the needy people.Eid al-Adha falls on the same day of the Islamic calendar. But, on the Gregorian calendar, the date varies from year to year. The Gregorian calendar is a solar calendar whereas the Islamic calendar is a lunar calendar. The lunar calendar is 11 days shorter than the solar calendar. Every year, Eid al-Adha falls on different Gregorian dates in different parts of the world. This is due to the periphery of crescent visibility is different from the International Date Line.