Endocrinology can be defined as a branch of biology that mainly deals with the study of endocrine system and related functions, secretions and diseases. Endocrine system contains various glands. Every gland has its own secretion, known as hormone that perform specific functions. Clinical endocrinology is a branch of medical sciences that involves the diagnosis, cure, prevention and treatment of irregular secretion and modified action of hormones. Molecular endocrinology, basically deals with the study of various functions of hormones secreted by different glands, at molecular level.