The term measurement traceability is used to refer to an unbroken chain of comparisons relating an instrument's measurements to a known standard.
Calibration to a traceable standard can be used to determine an instrument's bias, precision, and accuracy.
It may also be used to show a chain of custody - from current interpretation of evidence to the actual evidence in a legal context, or history of handling of any information.
In many countries, national standards for weights and measures are maintained by a National Measurement Institute (NMI) which provides the highest level of standards for the calibration / measurement traceability infrastructure in that country.
Examples of government agencies include the National Physical Laboratory, UK (NPL) the National Institute of Standards and Technology (NIST) in the USA, the Physikalisch-Technische Bundesanstalt (PTB) in Germany and RISE (Research Institutes of Sweden)