The term applied to musical techniques employed in specific musicalgenres during specific musical eras. Quite often, performance practice refers to techniques that are implied, and not written or notated. Some examples would include the technique of using vibrato in some forms of jazz. Although not always notated, certain styles of jazz expect the use of vibrato. Ornamentation has changed throughout the years and the interpretation of most of the common ornaments need to be performed in the style appropriate to the era.