"Well I guess my music came to prominence around one piece called 'In C' which I wrote in 1964 at that time it was called 'The Global Villages for Symphonic Pieces', because it was a piece built out of 53 simple patterns and the structure was new to music at that time"

Terry Riley's quote is describing his composition "In C" which he wrote in 1964. At the time, it was called "The Global Villages for Symphonic Pieces" due to its unique structure. The piece was composed of 53 simple patterns, which was a new concept in music at the time. This structure was the beginning of Riley's musical profession and helped him acquire prominence in the music world. The piece was advanced in its structure and helped to form the modern music landscape. It was a major impact on the minimalist music movement and has actually been covered by lots of artists since its release. The success of "In C" has permitted Riley to continue to develop and innovate in the music world, and it is still considered among his most influential works.