Please tell me what this does.  I see no actual functionality for it.

It relates to grouping objects (Object > Create Grouping), which basically creates a "Null" object that you can use as a parent to other objects. Then you can set visibility or move the children of those grouping objects at the same time. Search the help for Grouping Objects for more information.(or navigate to Poser Reference Manual > Building Scenes > Props > Grouping Objects.)

@DCArt - thanks.  I wasn't aware. I was already creating my own controller props and parenting all the other stuff to it, then making it invisible.

Here's  one use of groups: I'm using them to show or hide groups of lights

@Y-Phil good idea. I have not tried that.  Thanks !

That will give you a way to show/hide, but not to turn them on/off by groups, for this you'll need a script such as one that I wrote

Y-Phil posted at 10:10 AM Sat, 10 December 2022 - #4451400

That will give you a way to show/hide, but not to turn them on/off by groups, for this you'll need a script such as one that I wrote