The present volume is mainly intended to serve as a reference book and class text in technical drawing. The content of the book includes numerous problems that cover literally every single phase of the subject; it is also constituting a full teaching unit. The authors have been encouraged in their initial aim by the extensive use of the text of this volume during the past several decades, and that aim was to prepare a tool which would be teaching the engineering language and to keep it duly updated with the latest developments. The original idea was to explain and illustrate each of the fundamental principles from the student's standpoint and to make the content interesting enough so that the students can read the book and study on their own initiatives. This fourth release of the book constitutes the thorough revision that the text did undergo. In fact, very small part of the original text and illustration has remained from the previous edition of the book. A huge number of new problems and informative illustrations have been added and hundreds of the old illustrations have been completely redrawn. The entire content of the book has been revised in order to duly reflect the latest recognized American Standards. Another improvement to the content is the adoption of a new format permitting the reproduction of illustrations larger for easier use.