Butter is a dairy product made by stirring fresh or fermented cream or milk. It is consumed spread on other dishes, as a condiment and it helps to cook or to make sauces or roasts. So, the butter is ate daily in many parts of the world. Butter consists in fat which is surrounded by tiny droplets of water, protein and milk. The most common type of butter is made from cow's milk, but also it can be obtained from the milk of other mammals, including sheep, goat, buffalo or yak. Sometimes you can add in butter salt, flavors, or preservatives.   

Cream is a dairy product made by fat which rises to the surface of non-homogenized milk. Cream is obtained from cow or buffalo milk, unboiled, put in a bowl to caught (curd) in a cool dry place. After a few days fat milks rise to the surface in a thin or thicker crust , depending on the milk fat. This time of few days is shortened in industrial processes for obtain cream using centrifugals named cream separators.

Yogurt is a dairy product made by milk fermentation. Any milk may be used to produce yogurt, but today, cow's milk is the most commonly used. Yogurt has a texture like a gel and taste slightly sour because of fermentation of sugar from milk (lactose) into lactic acid.

Kefir (aka the kefirs) is a milk product made by fermented milk; it”s originated in the Caucasus area. It is prepared by introducing kefir grains in milk from cows, goats or sheeps. Traditional kefir was made in waterskins (bottles) that were hung near a doorway; anyone passing by hit the waterskin in order that milk and kefir grains to mix well.