Other revisions and updates include the addition of frontend Learning Objectives; elimination of weak problems and addition of new problems; more relevant and current case studies as well as additional new ones where appropriate; new chapter on Rapid Prototyping; expanded coverage of non-metallic materials such as composites, polymers, etc. ; a discussion about sustainability and green, and engineering and how it relates to manufacturing; coverage of lean manufacturing and production; and updated references and chapter summaries.