--- a/LuaOverview.wiki	Sun Jun 07 00:13:06 2020 +0200
+++ b/LuaOverview.wiki	Sun Jun 07 04:18:15 2020 +0200
@@ -59,3 +59,12 @@
 
 Hint: On [http://www.colorpicker.com/] you find a color-picking tool for getting RGB colors easily.
 
+=== Coordinates ===
+Every position on the map can be addressed with Cartesian coordinates: X and Y. Those are integers.
+
+* X is the horizontal axis. It starts at 0 on the left side of the map and increases when you go right
+* Y is the vertical axis. It starts at 0 at the top of the map and increases when you go downwards
+
+X and Y can be negative when you go above or left of the map boundaries.
+
+Some global variables contain important coordinates, see [LuaGlobals].
\ No newline at end of file