LASH is the abbreviation for "Lighter aboard Ship" and refers in principle to a ship within a ship. These are cargo ships that transport container ships without their own propulsion.
These can be barges, embossments or lighters. The LASH is used to transport inland waterway vessels that have to move on waterways separated by seas. In the port of destination, the carrier ship separates again from the vessel, which is then usually moved on the inland waterways as a pushed train. The containers are mainly used to transport heavy goods and forest or metal products. In the meantime, however, this type of ship has been almost completely replaced by container ships.