This book covers the fundamentals of biology. It is primarily aimed at students completing school biology courses or about to start a biology degree course. It summarises the biology that ought to be seen as essential at those stages and corrects the most common misinterpretations that tend to occur. The fact that all aspects of biology are interlinked is highlighted. The book also emphasises that biology is not just about humans, or vertebrates, but that an appreciation of the vast diversity of life is important to a proper understanding of the subject.