When properly designed, flow maps are beneficial because they allow cartographers, GIS analysts and map users alike to easily see the differences in magnitude of a wide variety of items across space with very little map clutter (Phan, et al). This in turn allows businesses to see where the majority of their products are going, commuters to see traffic patterns, and meteorologists to see wind patterns.
This article provides a basic overview of flow maps and a description of how they work. It also describes the three different types of flow maps and explains the characteristics and components of a good flow map. Finally it presents several examples of different types of flow maps