from http://www.designillustration.com/BCC3/oct30_5.htm
The Pathfinder palette contains several tools to combine single paths, many times overlapping paths, into more complex paths. Paths can be merged together, subtracted from one another, and dissected into discrete segments.
- A screenshot would be nice. --bb
Here it is:
upload:illy_cs_pathfinder.png
Shape modes (left to right): add to shape area, subtract from shape area, intersect shape areas, exclude overlaping shape areas
Pathfinders (left to right): Divide, Trim, Merge, Crop, Outline, Minus back