Georgios Papanikolaou was a Greek physician and researcher, best known for developing the Pap test, a screening procedure for cervical cancer. Born on May 13, 1883, in Kymi, Greece, he moved to the United States in 1904, where he conducted significant research in cytology, the study of cells. Papanikolaou's work revolutionized women's health by enabling early detection of cervical cancer, significantly reducing mortality rates. His contributions to medicine earned him recognition, and he is often referred to as the "father of the Pap smear." He passed away on February 19, 1962, leaving a lasting legacy in cancer prevention.