This chapter includes a description of lateral force microscopy (LFM), also known as frictional force microscopy (FFM). LFM description includes an explanation of cantilever behavior during LFM imaging. This chapter also includes an explanation of tip-sample interactions during imaging. Readers will also find information regarding the interpretation of LFM data, particularly interpretation of the friction loop. At the end of this chapter, readers will find a laboratory investigation that involves the deposition of a thin polymer film on a substrate, and etching the film using the AFM tip as a scribe. The lab includes a friction loop analysis of the shaved and unshaved areas.