Adha, a period of "communal enjoyment" for Muslims worldwide, has officially arrived. Here's what we've learned about the Islamic holiday.

Adha, the festival of sacrifice by offering prayers in mosques and open spaces before sacrificing animals. (AP video by Muhammad Farooq, Shonal Ganguly and Al Emrun Garjon)

Less spending, higher prices and fewer animal sacrifices subdued the usual festive mood as the Muslim holiday of Eid al-Adha was celebrated in many parts of the world.