When you select a group Hyperglance shows you a summary pane that aggregates all the entities and shows you their status.

There are 4 tabs available with the initial summary tab being the initial default. The others tabs are Group Attributes, Group Metrics and an Alarm tab. All alarms in the group are aggregated; this means any alarms the group itself has as well any alarms on any sub-nodes(etc) are all displayed here.

The group summary panel is comprised of a little stats chart per type of node contained within that group:

In the next figure you can see the donut chart for "Account" nodes.
The big number in the center of the donut is the total number of Account entities that belong to that group.
You can also see the percentages of entities based on their current Alarms or runtime states by clicking on the button at the top of the donut list. "Alarms" is selected by default.
In this example the group has 3 Accounts, out of those 2 have Alarms of type "Warning" and  the remaining 1 is OK (No Alarms present):

If you hover over a section of the donut you will see be able the see the percentage of nodes  represented by the actual number.

You can click on the donut chart (or around it) to bring up an inventory table listing all the S3-Buckets contained with this group:

1. Click on a donut or in the area around it
2. Inventory table of entities corresponding to that type (in this case S3-Bucket of datasource Amazon).

3. Search - both Simple and Advanced search are explained in detail here