PDMWorks Enterprise for SolidWorks

What's different between PDMWorks Enterprise for SolidWorksand PDMWorks Enterprise Contributor, because we're test on somemachine that doesn't have SolidWorks software and check in *.sldprtfile. it's can checkin and work well,
thus, what's exact differrent between this two module.SolidworksSolidworks Pdm enterprise Pdm