Gin is a flavored spirit that is created by redistilling a high proof neutral spirit in the presence of juniper berries and other flavoring agents. Franciscus Sylvius, a Dutch physician and professor of medicine at the University of Leyden, is credited with the invention of gin in the seventeenth century. Originally named Genièvre – the French word for Juniper berry, it was shortened to Gin by the English later in the late 17th century. Gin gets its distinctive flavor from the various botanicals it is redistilled with. Some common ingredients include juniper berries, cassia bark, coriander and angelica root. The four distinct varieties of gin are Plymouth, London Dry, Dutch and Old Tom.