Eid Mubarak to my Muslim readers! Eid al-Adha is a Muslim holiday that celebrates they end of Hajj. Hajj is the pilgrimage to Mecca that all Muslims must do at least once in their lifetime. During Eid al-Adha, Muslims remember the trials of Abraham, a Muslim (and Jewish) prophet, by slaughtering an animal. The animals most commonly slaughtered are: sheep, camels, or goats. While slaughtering the sacrificial animal, the name of Allah is spoken, to remind Muslims that life is sacred. One third of the sacrifice is is eaten by immediate family and relatives, one third is given away to friends, and one third is donated to the poor. This sacrifice doesn't atone for sins, but instead is a mark of piety.
Muslims start off the day by attending the Mosque, visiting friends and family, exchanging good will and gifts, and then visiting a farm to slaughter their sacrificial animal.