Basic Coordinate System
The cursor can be moved in the working window by using the mouse. The exact location of the cursor in the working window is determined by coordinates. Two coordinate systems are used: an absolute coordinate system and a relative offset coordinate system.
Absolute Origin
In an absolute coordinate system, the drawing window origin is 0x,0y regardless of the cursor location.
In the drawing window, the absolute origin locates in the left lower corner of the drawing limits, when a new drawing is created.
The X,Y coordinates indicate the distance between the cursor and the absolute origin. Click the status bar to display the coordinates X, Y in the right end of the status bar.
Local Origin
The origin of a relative coordinate system, or the local origin, is located in the point last selected. In other words, the location of the local origin changes as points are selected.
The coordinates dx,dy show the distance of the cursor from the point last selected. The status bar displays these coordinates by default. You can view the coordinates X,Y and dx,dy in turns by clicking the status bar.