What is a heat map in Tableau?

A heat map in Tableau is primarily defined as a visualization using color gradients to display values across two dimensions. This type of visualization enhances the viewer's ability to quickly identify patterns, trends, and anomalies within the data by representing data intensity through variations in color.

In this context, the significance of color gradients allows for an immediate visual interpretation of how different values or measurements compare with one another within the dataset. For instance, higher values might be indicated by warmer colors, while lower values are represented by cooler colors. This attribute makes heat maps especially useful for data analysis tasks that require deciphering complex datasets at a glance.

The other options describe different forms of visualization or data representation but do not align with the specific characteristics of a heat map in Tableau. An interactive map, for instance, focuses on geographic data representation, while a series of graphs would indicate a comparative analysis and a linear graph is specific to showing trends over time. None of these encapsulates the essence of what a heat map provides in terms of visual data analysis.