Two thirds of our planet is covered by oceans and seas. Over recent decades, developments in ocean science have dramatically improved our understanding of the key role oceans play in the Earth's system, and how vital they are for regulating global climate. Humans depend on the oceans for many resources, but, at the same time, their impacts on the marine systems around the world are of increasing concern. Introducing Oceanography provides a succinct overview of the science of the study of the seas and is a topical guide to this enormous and complex subject.