Learn how to use the Image Overlay Heatmap data visualization. Image Overlay Heatmap charts are a type of Relationship charts. Relationship charts are suited to showing how one variable relates to one or more other variables. You use relationship charts to show correlation or connections between variables in a data set. Heatmaps charts are good for showing how something positively effects or negatively effects another variable over time. Image Overlay Heatmaps are well suited for IoT analytics use cases. For example, upload a building floor plan image to show where sensors are deployed and their health with drill-down capabilities to see specific device details.