What is piano arrangement?
In music, an arrangement is a musical reconceptualization of a previously composed work. It may differ from the original work by means of reharmonization, melodic paraphrasing, orchestration, or development of the formal structure. ... Arranging is the art of giving an existing melody musical variety".
What is arranging in music production?
Arranging can broadly be defined as the process of transforming a collection of musical ideas into a complete track. It can involve everything from writing harmonies, re-arranging parts, adding parts, removing parts, planning the structure of a song or even adding effects from time to time.