The adipose tissue, also known as fatty tissue, is a loose connective tissue composed mainly of fat cells (adipose cells, or adipocytes). It is mostly found beneath the skin but also presents between the muscles, around some important internal organs for protecting from mechanical damages and deposits in the membrane folds of the intestines or other parts of the body. The two types of adipose tissue are white adipose tissue and brown adipose tissue. White adipose is the most common type which bears the energy store for times of great exertion or starvation and provides pads for organs. The hydrolysis of triacylglycerol in adipose cells occurs when muscles or other tissues of the body need energy, which results in the release of energy-rich fatty acid and glycerol. Brown adipose produces heat for the body when stimulated by cold which found mainly in newborns. The distribution of adipose tissue in the body varies between males and females. And too much or too little adipose tissue may raise severe health implications. A variety of target molecules on adipose tissue are applied to detect related conditions.