What are the major terminologies related to Instrument calibration?

Accuracy - The degree of an indicated value to an accepted standard value or true value.

Calibration - correcting or determining the error of an existing scale or of evaluating one quantity in terms of reading from another.

Factory calibration - adjust all the internal working of the instrument to bring it into agreement with the standard.

Field calibration - compare one instrument with another instrument.

The other important terms are

Error - Measurement error is the difference between the measured value of a quantity and its true value. Precision - Precision refers to how close together a series of measurements are to each other. Resolution Repeatability Reprocucibilty Traceability Accuracy - Accuracy refers to how close a measured value is to an accepted value.