Differences, where they exist, are shown in Appendix A with associated rationale. This SAE Standard defines the most commonly used terms for piston rings. These terms designate either types of piston rings or certain characteristics and phenomena of piston rings. The terms and definitions apply to piston rings for reciprocating internal combustion engines and compressors working under analogous conditions. Appendix B is included which lists equivalent terms in English, French, Russian, German, Spanish, Portuguese, Italian, and Japanese.