This part of ISO 5436 defines Type F1 and Type F2 software measurement standards (etalons) for verifying the software of measuring instruments. It also defines the file format of Type F1 software measurement standards for the calibration of instruments for the measurement of surface texture by the profile method as defined in ISO 3274. NOTE 1 Throughout this part of ISO 5436, the term “softgauge” is used as a substitute for “software measurement standard Type F1”. NOTE 2 Formerly, “measurement standards” were referred to as “calibration specimens”. NOTE 3 ISO 3274 only refers to instruments with independent reference datums.