The Angiosperm Phylogeny Group, or APG, refers to an informal international group of systematic botanists who came together to try to establish a consensus on the taxonomy of flowering plants (angiosperms) that would reflect new knowledge about plant relationships discovered through phylogenetic studies. As of 2010, three incremental versions of a classification system have resulted from this collaboration published in 1998, 2003 and 2009. In the past, classification systems were typically produced by an individual botanist or by a small group. The result was a large number of systems. Different systems and their updates were generally favoured in different countries. Keeping in mind the requirement of good contents for students, this book is covers the Principles of Angiosperm Taxonomy and their families, Classifications, Nomenclature, Biosystematics, Modern Trends in Taxonomy, Chemotaxonomy, Numerical Taxonomy etc. loaded with numerous appendices like comparison of classifications, floral diagrams and floral formulae, questions etc. This book will develop in the student an understanding of the principles of this subject. In order to make the subject simple and interesting every topic included in this book has been self-sufficient in itself and has been explained in the light of modern development in a simple and elegant style.
