Split Normal Quantile Plot
You can use split normal quantile plots to assess the normality of distributions of some attribute across various groups. There is one normal quantile plot for each group. (To split a normal quantile plot, drop an attribute on the axis not occupied by the numeric attribute.)
Here, we see some (manufactured) data for two groups. One is normal, the other is non-normal.
An normal quantile plot shows the distribution of continuous (numeric) data. There is one point for each case.