Layer groups organize objects so that vGIS users can turn multiple objects on and off at once. For example, if your data set contains water, sewer, and storm water assets, you may create Water, Sewer, and Storm Water layer groups to combine related assets in just three groups. You can always create more layer groups later.
To add a new layer group, click on the global "+" sign on the top left corner of the portal and select the Layer Group option. Complete the setup wizard and click "Save".
To learn more about Layer Groups and how and why to apply them, follow this link.