Which jobs did George Gershwin hold before becoming a famous composer?

Before achieving fame as a composer, George Gershwin held several roles that helped refine his musical skills and dexterity. After leaving school at age 15, he worked in the following capacities:

• Piano roll creator: He produced piano rolls for player pianos.12
• Nightclub pianist: He performed in various New York nightclubs.12
• Song plugger: He worked for the Jerome Remick music-publishing company in Tin Pan Alley, where he demonstrated sheet music to potential customers.12
• Accompanist and rehearsal pianist: He served as an accompanist for popular singers and as a rehearsal pianist for Broadway musicals.12

These early experiences were instrumental in developing his abilities in improvisation and transposition, eventually leading to his success as a writer of popular songs and jazz-influenced classical compositions alongside his brother, Ira.12