Such a WRONG title. A giesga is a fine arts entertainer. This title is like saying all singers are prostitutes. Geisha are professional female entertainers who perform traditional Japanese arts on banquets.
Girls who wish to become a geisha, have to go through a rigid apprenticeship during which they learn various traditional arts such as playing instruments, singing, dancing, but also conversation and other social skills. In Kyoto, geisha apprentices are called "maiko".