Information is a crucial component in any productive process. Apart from having the known factors of production, that is, land, capital, labor and enterprise, information is important for the purpose of locating, acquiring, and integrating those factors of production to make them bear the expected results. This means that information managers are increasingly being faced with the challenge of being even keener as they provide information to their clients. It is important for the information managers to avail information in an environment more easy to access, retrieve and use, by the information users. Classification is one of the very vital tools to enable information managers attain this goal. This book focuses on classification of information materials and all the aspects that entail classification. These include abstracting, Thesaurus, Classification schemes and many other aspects. The book is helpful to Middle level Colleges and University Students, Information managers, Librarians, Lecturers and other stakeholders in information management.