The history of pharmaceutical education has closely followed that of medical education. As the training of the physician underwent changes from the apprenticeship system to formal educational courses, so did the training of the pharmacist. The first college of pharmacy was founded in the United States in 1821 and is now known as the Philadelphia College of Pharmacy and Science. Other institutes and colleges were established soon after in the United States, Great Britain, and continental Europe. Colleges of pharmacy as independent organizations or as schools of universities now operate in most developed countries of the world. The course of instruction leading to a bachelor of science in pharmacy extends at least five years. The first and frequently the second year of training, embracing general education subjects, are often provided by a school of arts and sciences. Many institutions also offer graduate courses in pharmacy and cognate sciences leading to the degrees of master of science and doctor of philosophy in pharmacy, pharmacology, or related disciplines. These advanced courses are intended especially for those who are preparing for careers in research, manufacturing, or teaching in the field of pharmacy.