Eid ul - Adha

In Malaysia, it is more commonly known as Hari Raya Korban or Hari Raya Haji and a public holiday is observed.

Celebrated about two months after Aidilfitri, on the 10th day of Zulhijah, the 12th month of the Muslim calendar, it marks the end of the haj pilgrimage period (about two weeks); hence the name Hari Raya Haji (festival of the pilgrimage).

During Aidiladha, the sacrifice of animals such as lambs, goats, cows, bulls and camels is performed. The animals are slain in accordance with the proper religious rites; the meat is then distributed.

Taken from http://allmalaysia.info/msiaknow/festivals/rayahaji.asp