Program structure refers to the organization and arrangement of various components within a software application or system. It defines how the program's elements, such as functions, modules, classes, and data structures, are organized and interact with each other. A well-structured program enhances readability, maintainability, and scalability by dividing complex tasks into smaller, manageable units. It also ensures efficient collaboration among developers, clearer documentation, and easier debugging. The structure can vary depending on the programming paradigm used, such as procedural, object-oriented, or functional programming, but its primary goal is to ensure that the program is logical, efficient, and easy to understand.