A destroyer tender or destroyer depot ship is a type of depot ship: an auxiliary ship designed to provide maintenance support to a flotilla of destroyers or other small warships. The use of this class has faded from its peak in the first half of the 20th century as the roles and weaponry of small combatants have evolved.
The destroyer tender Klondike with a flotilla of Allen M. Sumner-class destroyers, Subic Bay, Philippines, November 1963
An auxiliary ship is a naval ship designed to support combatant ships and other naval operations. Auxiliary ships are not primary combatant vessels, though they may have some limited combat capacity, usually for purposes of self-defense.
German Navy Berlin-class replenishment ship
Royal Canadian Navy auxiliary oiler HMCS Preserver during New York fleet week, 2009
Australian oiler HMAS Sirius refueling USS Essex, June 2007
American cargo ship USNS Furman, 1981