The endocrine system uses glands, hormones, and feedback mechanisms to regulate the body. It helps the nervous system maintain balance. Primary glands include pituitary, thyroid, parathyroid, adrenal, and gonads, pancreas, and hypothalamus. Specific hormones are released by each gland into the bloodstream, stimulating or inhibiting target organs. Insulin regulates blood glucose levels, while thyroid hormones encourage growth and metabolism. Imbalances cause disorders like diabetes, thyroid disorders, and infertility.