Villancico, a form of Spanish song, was popular throughout the Renaissance period, although it may also be found earlier and later. It is a literary and musical style that may be sung with or without instrumental accompaniment. It evolved from a folk song, typically with a devotional hymn or love poem as text, into an art music genre. The term "villancico" comes from the Latin word for "whistle." The first known reference to a "villacico" appears in a book by Antonio Pucci called Le piacevoli e nuove scienze (The Pleasant and New Sciences), which was published in 1556. Villancicos were popular throughout Europe, especially in Spain, Italy, and Germany. They often included sections called jotas (little tunes) that could be danced to. In addition to being used as entertainment, villancicos were also employed as prayer songs by nuns and priests. These songs, called vihuelas because they usually used a violin as a backing instrument, were important for spreading news about religious events and changes in church politics. A famous vihuelista was Gaspar de Salinas, who worked with Thomas Morley to create a standard notation system for musicians to play their parts from. Gaspar de Salinas died in 1613 at the age of 36, but his work lived on through Morley's library of music.