On a nautical chart the distance is often measured on the latitude scale appearing on the sides of the map: one minute of arc of latitude is approximately one nautical mile or 1852 metres. An ECG (also EKG) caliper transfers distance on an electrocardiogram; in conjunction with the appropriate scale, the heart rate can be determined.A pocket caliper versions was invented by cardiologist Robert A. Oddleg calipers, Hermaphrodite calipers, or Oddleg jennys, as pictured on the left, are generally used to scribe a line a set distance from the edge of a workpiece.The calipers in the diagram show a primary reading on the metric scale of about 2.475 cm (2.4 cm read from the main scale plus about 0.075 cm from the Vernier scale).Calipers often have a "zero point error", which is when the calipers do not read 0.000 cm when the jaws are closed.The bent leg is used to run along the workpiece edge while the scriber makes its mark at a predetermined distance, this ensures a line parallel to the edge.
These calipers comprise a calibrated scale with a fixed jaw, and another jaw, with a pointer, that slides along the scale.
Assuming no systematics affect the measurement (the instrument works perfectly), a complete measurement would then read 2.462 cm ± 0.005 cm.
The vernier, dial, and digital calipers give a direct reading of the distance measured with high accuracy and precision.
A caliper (British spelling also calliper, or in plurale tantum sense a pair of calipers) is a device used to measure the distance between two opposite sides of an object.
A caliper can be as simple as a compass with inward or outward-facing points.