Why do historians divide history into periods or eras?

Historians divide history into periods or eras to create a structured framework that helps organize and analyze the vast complexities of human experience over time. This segmentation allows for the identification of significant social, political, economic, and cultural changes, making it easier to understand patterns and developments. By categorizing history, historians can also facilitate comparisons between different times and places, thereby enhancing our understanding of continuity and change. Additionally, these divisions often reflect major events or transformations, providing a clearer narrative of historical progress.