What is the name for a plot that shows data at each X,Y coordinate

I'm creating some new plotting infrastructure and I can't figure out what this type of plot should be called.

It's a pretty basic plot where you have an Cartesian X-Y grid and each grid cell represents data for that X,Y coordinate. Sometimes those cells will contain continuous values which will be represented with a color gradient scale. In that case, I would call it a heatmap. However, sometimes it will contain Boolean data so I'll just have one color for true and one for false. That doesn't really seem like a heatmap to me. It's possible that some day I may add in other discreet value types (such as enums) where I'll just have a different color for each value.

Is there a term the covers both heatmaps and other heatmap-ish plots where you have discreet values?