They are so called because of the acronym of the English term roll on-roll off, referring to the procedure in which a means of transport is driven onto a ship as in this case by its own means, without any other loading equipment. These vessels have ramps that allow the cargo to be unloaded (roll off) and loaded (roll on); in contrast, lo-lo containers (lift on-lift off). Roro vessels indicate that they were designed in a risky way, which increases the probability of accidents, certain studies ha...