Cassava, Manihot esculenta, is also known as yuca root, yuca, manioc, and a number of other common names. It is a spurge which is native to South America. In the tropics, Cassava is a major source of carbohydrates - only rice and maize (corn) provide more. Preparations of cassava are also used as non-human animal feed.
Cassava contains cyanide which is removed when preparing the tuber to eat.
Cassava is now grown and eaten in tropical and sub-tropical regions throughout the world. As can be imagined it is prepared in many ways, given its wide distribution. Generally it is ground or pulped to make a flour, from there its preparation varies widely.
The photograph above was taken in a market in Panama.