AN INTRODUCTION TO MECHANICS OF MATERIALS attempts to deal with the subject as an engineering science with a clear elaboration of the central scheme of dealing with this subject, namely, delinking the geometry aspects of the subject from the materials aspects. This is achieved by using explicitly the three-step scheme of macro (forces) to micro (stresses) conversion, transforming at the micro level (from stresses to strains), and then converting back to the macro level (deformations), or vice versa. Another aspect which has been emphasised considerably is the construction of idealized models of the physical structures such that they are amenable to analysis with the mathematical tools available with a beginning engineering student. The level of mathematics used has been kept at the very minimum, without sacrificing the rigour. In the belief that not all readers would have sufficient familiarity with the engineering aspects of many applications discussed, considerable amount of details about these have been included wherever feasible.