How do they secure 40' containers to the ship and each other?

40' containers are secured to the ship using twist locks at each corner, which lock the containers to the ship's deck and to one another. Additionally, lashing rods or straps are often employed to further stabilize the containers and prevent movement during transit. The containers are arranged and stacked in a way that maximizes balance and minimizes the risk of shifting, ensuring safe transport. Regular inspections are conducted to ensure the integrity of these securing methods throughout the voyage.