Both types of IUDs work primarily by preventing sperm from fertilizing an egg. The copper IUD releases copper into the uterus, which works as a spermicide. The others release a form of the hormone progestin into the uterus. The progestin thickens the cervical mucus so that sperm can't reach the egg.
Commercial agriculture. Commercial agriculture is a large-scale production of crops for sale, intended for widespread distribution to wholesalers or retail outlets. In commercial farming crops such as wheat, maize, tea, coffee, sugarcane, cashew, rubber, banana, cotton are harvested and sold in the world markets.
Traditional economy. A traditional economy is any historical subsistence economy or one that otherwise falls outside the definitions of market or planned economies. A PURE traditional economy has NO changes in how it is done. Examples of traditional economies include those of the Inuit or those of the tea plantations in south India. Traditional economies are popularly conceived of as primitive or undeveloped economic systems, having tools or techniques seen as outdated.