What you call them depends on where they're made. A U-boat is nothing more than the Anglicized term for a German submarine and isn't strikingly different from U.S. subs. The whole "boat ...

Researchers from the “Eslabón Perdido” (Missing Link) team have come across a German Reichsmarine submarine off the coast of Necochea in the Argentine province of Buenos Aires near Arenas ...

German ships famously adopted an “unrestricted submarine war” policy at the ... Wilkinson approached Britain’s King George V with models of ships adorned in zig-zag and checkered patterns ...