For those with a curiosity about shores or a desire to better understand them, The Beach Book shares the basic science behind waves, tides, sea level, sand dunes, salt marshes, and beach erosion. It tells sunbathers why the beach widens and narrows from week to week and helps boaters and anglers understand why tidal inlets change. It gives home buyers insight into gauging erosion rates and provides natural-resource managers and concerned citizens with richer information on sediments, erosion control, beach nourishment, and coastal-zone development. Carl Hobbs also proposes methods.