Water covers more than 70 percent of the Earth but three quarters of our oceans' depths have never been explored by humans. This stunning book takes readers on a deep dive through the different depth zones--from the shoreline and surface, via the sunlight zone, the twilight and midnight zones, and into the abyss--to chart the richness and diversity of life in our seas.Each chapter, centered on a different depth zone, begins with a comprehensive introduction, before exploring fifteen to twenty-five visual themes, from the smallest living things to the largest and from the familiar to the unknown. A final chapter on the oceans and us reveals the visual history of human interaction with the deep blue, from discovery and mapping to current issues of the environment and preservation. Ocean features stunning photography throughout--from microscopic images of tiny creatures to corals of every hue and the abstract patterns of fish scales--shown alongside a wide range of stunning archival illustrations and specially commissioned infographics that convey complex data in a simple and elegant way.Exploring a huge range of themes, creatures, and plants from around the world, Ocean draws crucial attention to the importance of life in our seas and the need to preserve it.