Starcraft: Incgamers analyzes the defensive and offensive abilities of the Starcraft II Terran unit: The Raven.
This unit is a support ship that can protect your base while your troops are elsewhere, but can also benefit your infantry with invisibility detection, missile interception and additional fire by dropping up to four auto-turrets which attack both ground and air units.
An additional ability must be researched and for a good reason. It's the most devastating ability of the Raven along with the Ghost's tactical nuke. Its name? The Seeker Missile.