PropertySets are lists of properties, and PowerShell sometimes adds PropertySets to result objects to make picking the right information easier. Get-Process for example returns process objects, and these contain two PropertySets:
PS> Get-Process | Get-Member -MemberType PropertySet TypeName: System.Diagnostics.Process Name MemberType Definition ---- ---------- ---------- PSConfiguration PropertySet PSConfiguration {Name, Id, PriorityClass, FileVersion} PSResources PropertySet PSResources {Name, Id, Handlecount, WorkingSet, NonPagedMe...
If you're interested in process configuration, you can use the PropertySet PSConfiguration to display the typical process properties Name, Id, PriorityClass, and FileVersion. If you rather want to keep an eye on process resources, use the PropertySet PSResources instead:
PS> Get-Process | Select-Object -Property PSConfiguration PS> Get-Process | Select-Object -Property PSResources
Note that in PowerShell 3.0, the parameter -Property supports auto-completion, so just enter "PS" and then press TAB to see all properties that start with "PS".