A
bulkhead is an upright wall within the
hull of a
ship. Other kinds of partition elements within a ship are
decks and
deckheads.
The word bulki meant "cargo" in Old Norse. Sometime in the 15th century sailors and builders in Europe realized that walls within a vessel would prevent cargo from shifting during passage. In shipbuilding, any vertical panel was called a "head". So walls installed abeam (side-to-side) in a vessel's hull were called "bulkheads." Now, the term bulkhead applies to every vertical panel aboard a ship, except for the hull itself.
Bulkheads in a ship serve several purposes
Some bulkheads and decks are fire-resistance rated to achieve compartmentalisation, a passive fire protection measure.
