A surface, especially of a curving form

A circular object is a curving form

The gregorian chant was a major cultural milestone in the middle ages. it was one of the first codified forms of music meant to be played as written, where previously it was difficult to mass-produce and disseminate any music. what's more, these chants were also some of the first examples of musical notation: the notes and bars of today's music sheets are a reflection of centuries of evolution beginning with these chants. it became official throughout the entirety of the catholic church, meaning that nearly all of europe followed this musical notation and styling.

Heyaas we all know that history is the most important without it we cant solve anything. i had never read any history thats why i dunno know about any past culture.we can read it via wikipedia. u