What is the purpose of the 'instrument function' in EarSketch?

The purpose of the 'instrument function' in EarSketch is to add specific musical instruments or sounds to a track. This function allows users to select from a variety of built-in instruments and sounds to enhance their music compositions. By utilizing the instrument function, you can create more dynamic and interesting tracks by layering different sounds and exploring various musical styles. This capability is crucial for building a rich audio experience and helps users express their creativity effectively while composing music within the EarSketch environment.