A high resolution polygonal mesh has more polygons than a low resolution mesh. A low resolution mesh with a rounded surface will appear faceted. A high resolution mesh has more polygons by which to articulate a rounded surface and will appear to be rounded at a closer range. More polygons also means that the mesh can be more detailed. While it's possible to create a high resolution surface on a low resolution mesh by means of a displacement map sculpted in Zbrush or other sculpting programs, a high resolution mesh is more flexible in the Poser world since it has more morphing potential. Somebody recently posted that V3 has over 70,000 polygons. That is certainly high resolution. A low resolution Poser figure would be under 30,000 in my book. 

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