Story highlights Eid al-Adha commemorates when God appeared to Abraham

Eid Mubarak and Eid Saeed are greetings used during the holiday

Eid al-Adha is also known as the Feast of Sacrifice or Greater Eid

(CNN) Five things to know about Eid al-Adha:

1. Considered one of Islam's revered observances, the four-day religious holiday corresponds with the height of the Hajj -- the pilgrimage to Mecca in Saudi Arabia that annually draws 2 million Muslims.

2. Eid al-Adha commemorates when God appeared to Abraham -- known as Ibrahim to Muslims -- in a dream and asked him to sacrifice his son as an act of obedience. As Abraham was about to sacrifice his son, God stopped him and gave him a sheep to kill in place of his son. A version of the story also appears in the Torah and in the Bible's Old Testament.

3. Pronounced EED al-UHD-huh, the holiday begins Friday and ends Monday -- the last day of the Hajj . Eid al-Adha is also known as the Feast of Sacrifice or Greater Eid. It is the longer of two Eid holidays observed by Muslims. Eid al-Fitr -- or Little Eid -- follows the conclusion of the holy month of Ramadan.

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