The thyroid gland is a small butterfly-shaped gland located in the front of the neck. It is divided into two lobes, connected by a narrow strip of thyroid tissue known as the isthmus. Structurally, the thyroid gland is organized in small follicles that store the thyroid hormones. Functionally, the thyroid gland is going to produce three hormones, triiodothyronine (T3), tetraiodothyronine (T4), and calcitonin. T3 and T4 play a crucial role in controlling our metabolism and they are also important for growth and brain development during childhood. On the other hand, calcitonin is involved in regulating calcium and bone metabolism.