You can trace the nodes of an object, for example, the Yucatan in Mexico using the Polyline or Polygon commands. This makes it easier to digitize objects that share a border because you do not have to re-digitize the shared border. You can also use this feature to trace an existing polygon/polyline network, for example, a street, a county, or some other polyline or boundary. A Status Bar entry displays showing that this mode is enabled.
To trace a border:
- Open a map layer you want to trace a polygon or polyline on.
- Make the layer that you want to work with editable. On the HOME tab, in the Windows group, click Tool Windows, and click Layers from the list, to open the Layers window.
You can also see map layers in the Explorer window.
Click the Editable
icon beside the layer name to turn On editing.Click the Selectable
icon beside the layer name to turn On selection. - Press the S key to turn on the Snap process and the T key to turn on Autotrace mode.
The words SNAP and AUTOTRACE display in the MapInfo Pro status bar, located along the bottom of the MapInfo Pro screen.
- On the SPATIAL tab, in the Create group, click Insert, and Polygon or Polyline from the list.
- On the map, click on the first node that you want to trace. Drag the mouse along the nodes of the line or object you want to trace.
The rules that apply to AutoTrace are:
- To enable the AutoTrace mode, you must use the Polygon
or Polyline 
commands. - You must press S to enable the Snap feature to use the AutoTrace feature.
You can use the Shift or Ctrl keys. When you auto trace a polygon, the path contains the least number of nodes necessary to complete the auto trace, which is similar to the Shift key behavior. If you want to trace the longer path, press the Ctrl key to override default auto trace direction. When you are auto trace a closed polyline, the trace line never crosses the start and end points of the polyline (so the Ctrl key has no effect).