What is a birds eye in piano?

In piano music, a "bird's-eye" or overview score is a smaller, condensed version of the entire musical piece that allows the pianist to see the arrangement of the entire song before playing it. It presents a simplified summary of the structure, key changes, and thematic sections, providing the pianist with an overall perspective and a roadmap of the piece. The purpose is to facilitate quicker learning and an improved understanding of the overall flow of the music, especially when navigating through longer or complex pieces. By having a bird's-eye view of the entire score, pianists can gain a holistic understanding of the composition and make musical choices informed by the broader context of the piece.