The thyroid cartilage, the largest and most noticeable cartilage of the larynx, protrudes forward, forming what's usually called the Adam's apple. If you put your fingers on your throat and hum, you should feel the vibrations of your vocal cords under your fingers. During adolescence, this thyroid cartilage enlarges in males and is considered one of the secondary sex characteristics, along with growth of facial and pubic hair. The larger larynx is what causes men to have deeper voices than women.
Named after the Biblical story of Adam eating forbidden fruit in the Garden of Eden, the protrusion does resemble a small apple under the skin that bobs up and down while a person drinks. Hoarseness, pain or swelling in the area of the neck near the Adam's apple could signify anything from a cyst or polyp of the vocal chords to cancer of the thyroid or larynx cancer. An Ear, Nose and Throat (ENT) doctor is the first address to go to for a diagnosis.