Over the last quarter of the last century there were many changes in the maritime scene. Ships may now be much larger; their speeds are generally
higher; the crews have become drastically reduced; there are many different types (including hovercraft, multi-hull designs and so on); much quicker and more accurate assessments of stabiHty, strength, manoeuvring, motions and powering are possible using complex computer programs; on-board computer systems help the operators; ferries carry many more vehicles and passengers; and so the list goes on. However, the fundamental concepts of naval architecture, which the authors set out when Basic Ship Theory was first published, remain as vaHd as ever.