The discussion in this section applies to plots that show individual markers.
If you click an observation in a plot, a label appears near the selected observation. By default, the label is the observation number (position in the data table). You can choose instead to label observations by the value of any variable, called the label variable. You can set a default label variable that is used for all plots, or you can set a label variable for a particular plot that overrides the default label variable.