I am betting neither you nor I have used the User Groups feature in the Mac OS too much. Especially as a single computer user. However, if you are in a work environment where several people need to use one computer, then creating a User Group on that Mac may be a good idea. This is what you do to create a User Group on a Mac.
Here is what Apple says about User Groups:
A group allows multiple users to have the same access privileges. For example, you can grant a group specific access privileges for a folder or a file, and all members of the group have access. You can also assign a group specific access privileges for each of your shared folders.
I think User Groups are primarily used in a work environment. However, you could do this with a shared computer at home as well. You create a User Group in the Users & Groups System Preference Pane:
Click on the “Plus” symbol to add the account. You will get this drop down menu:
Select “Group” from the drop down and then click “Create User”. You will be asked to name the Group:
Once you click on Create Group, the group appears in the left sidebar of the User & Groups Preference Pane:
Click on the new group and select the users to appear in that group. That presupposes that each person has a Standard User Account on this particular Mac.
So what do you do with this new group? I think one of the most obvious uses is File Sharing, Printer Sharing, etc. Once your group is created go into the Sharing System Preference Pane click on File Sharing then the “Plus” symbol under the “Users” box. It produces a drop down menu. Click on the group name and then “Select” and the new group is added to File Sharing:
For something like Printer Sharing you do the same thing. Select Printer Sharing in the left sidebar, click the “Plus” symbol under “Users”, click on your new group and then “Select”:
The new group will be added to Printer Sharing:
Again, you may not need to do this from a home system, but if you do not have enough computers to go around, you may end up using this method.
If you do not need information on adding a User Group to your Mac, then maybe you could just tuck this info away for future use. You may need to use it at your work. Either way, it does not hurt to have it somewhere in the back of your brain.