Trees are in nature but also in our minds. Their shape have influenced how we communicate via diagrams, link ideas together and illustrate deeper human thoughts in art throughout history. Trees have been a recurrent metaphor for mapping information in numerous scientific domains, such as biology, genetics, sociology and linguistics and information visualisation is a growing area of interest amongst a variety of business practices. This book will expose our long-lasting obsession with trees, as metaphors for organising and representing hierarchical information, and provide a broad visual framework for the various types of executions, many dating back hundreds of years.