From the Alarm Summary Display, the SORT alarm field indicates how alarms are sorted: by Time (default), Name, Priority, Acknowledge Status and Alarm Group.
Clicking the square button next to each sort method will change the sort criteria.
This allows users and operators to quickly identify the Highest Priority Alarm, find an alarm by Tagname or other criteria. If the Alarm Filter is enable, those tags will be hidden from this sorted list.
Leaving the Alarm Summary, then returning will result in the sort by Time (the default value).
See also, Alarm Filter.