Mariachi is a musical expression originated from around the 18th tp the 19th century in Mexico. It is a tradition for the western mexicans. The mariachi contains a orchestra of violins, harp and guitars which developed in and around Jalisco. The word originated as mariache and then from that, it went on being mariachi. It means "Street Singer" in mexican spanish and started to gain more reconishion in 2010 and 2011!
Use ser in the correct form. For example, "Yo SOY de Nueva York" means "I am from New York." The same as "Tú eres de Bogotá." Which is "You are from Bogotá." Remeber to put in the "de".