What is the difference between flat bottom and shaped hull of a vessel?

First the hull is the part of a boat or ship. The Hull may have a variety of chine designs such as - S-shaped chine, single 'v', flat, 3 chine or multi chine.

The flat was the first made is easier to construct has good space to fill. however stabilty not so high when introducded to traverse currents or traverse waves.

The single v is the easiest to manufacture, lacks space and comfort.

3 chine is pretty common in small boats or sailboats.

multi chines used in kayaks for stability in a variety of conditions.

The S-shaped chine allowing for much better stability with a considerable portion under the water, good room or space. used more for big ships. but considerbly more difficult to build