This is a built-in turtle or link variable. It may hold a value of any type. The turtle or link appears in the view with the given value "attached" to it as text. You can set this variable to add, change, or remove a turtle or link's label.
See also label-color, plabel, plabel-color.
Example:
ask turtles [ set label who ] ;; all the turtles now are labeled with their ;; who numbers ask turtles [ set label "" ] ;; all turtles now are not labeled
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