In countries where tipping is expected (the United States for example), complicated unofficial standards and customs have developed over the exact percentage to tip, and what should and should not be included in this calculation. In other cultures where tipping exists it is more flexible and no specific assumptions of the tip amount exist.

The creation, performance, significance, and even the definition of music vary according to culture and social context. Music ranges from strictly organized compositions (and their recreation in performance), through improvisational music to aleatoric forms. Music can be divided into genres and subgenres, although the dividing lines and relationships between music genres are often subtle, sometimes open to individual interpretation, and occasionally controversial.

Servilius Damocrates (or Democrates, Greek: Δαμοκράτης, Δημοκράτης) was a Greek physician at Rome in the middle to late 1st century CE. He may have received the praenomen "Servillius" from his having become a client of the Servilia gens. Galen calls him άριστός ἰατρός, and Pliny says he was "e primis medentium," and relates his cure of Considia, the daughter of Marcus Servilius. He wrote several pharmaceutical works in Greek iambic verse, of which there only remain the titles and some extracts preserved by Galen.

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