Heatmaps are graphical representations of data where the individual values contained in a matrix are represented as colors. The color scale used in the heatmap indicates the magnitude of the value at each location in the matrix.

Heatmaps are often used to visualize patterns and correlations in data. For example, a heatmap could be used to visualize the relationship between two different variables, such as the temperature and humidity in a given location over time. The heatmap could show that as the temperature increases, the humidity also tends to increase or that there is a strong correlation between the two variables.