Traceology is defined as the study of wear marks and its history in criminology and archaeology is briefly described. It is proposed that the concept of traceology can be extended to machined surfaces, particularly those produced by abrasive techniques. A taxonomy of wear marks is outlined which would encompass both pits and scratches. Taxonomic implementations such as the morphology rose and the morphological tree are introduced. The general principles of traceology are illustrated by case studies from criminology, archaeology and abrasive machining processes.