From Teletraan I: The Transformers Wiki

The name Ark has been applied to lots of starships, including but probably not limited to:

• The Ark, the Vanguard-class starship from Generation 1 which usually crashed on Earth four million years ago.

• The Ark II, the Autobot starship that blew up in the Dreamwave Productions version of Generation 1.

• The Arc II, the oddly spelled Autobot starship that was hiding underwater in the G.I. Joe vs. the Transformers continuity.

• Various starships in the IDW Publishing Generation 1 continuity, including:

• Ark-17, the one that Springer used while rescuing Kup.
• Ark-19, Prowl's ship that's parked in Illinois.
• Ark-27, the one that's full of Triggerbots and Targetmasters... oh, and Gunrunner.
• Ark-32, the one headed towards Earth with Hot Rod and Hardhead on board.

• The Ark, the legendary ship from Transformers: Cybertron made up of the Atlantis, Ogygia, Hyperborea, and Lemuria.

• The Ark, the Autobot transport from the 2007 Transformers movie continuity.

Starships named Ark should not be confused with:

• The Axalon, the Maximal starship from Beast Wars.

• The other Axalon, the Autobot starship from Armada.

• The Autobots' small repair and transport ship in the Animated continuity that landed in Lake Erie.

• The state of Arkansas.

There is also a book called:

• Transformers: The Ark — A Complete Compendium Of Transformers Animation Models