Target, and target group
A target is one database on one registered server.
A target is one database on one registered server. Not the server — the database. The same connection appears as many times as you have databases on it:
Connection: sql-prod-01
Targets: sql-prod-01 / Sales
sql-prod-01 / Ops
sql-prod-01 / Archive
A target group is a named, ordered set of targets — "All Prod", "EU tenants", "The three that still run 2016". A group is a list of references; deleting a group deletes no connection and no database.
One group is selected in the command bar at a time, and that selection is where the next run goes. Nothing else determines it.