This document discusses the classification and maintenance of tractors. It defines a tractor as being derived from the words "traction" and "motor". Tractors are classified by their construction type, drive type, and purpose. Construction types include walking and drive types. Drive types are track and wheel. Tractor purposes include utility, row crop, orchard, industrial, and garden uses. The document also provides examples of common tractor troubleshooting issues such as failures to crank, start, or run properly due to problems like weak batteries, clogged filters, or needing rebuilt components.