Metrology simply refers to the science of measurement. However, metrology itself is a field of complexity that requires undeniably precise measurement tools. Backed by both theory and experimentation, metrology assesses the uncertainty that exists in measurement, and therefore impacts a number of other fields such as physics, mathematics, technology, engineering, and more. Metrology looks at accuracy, precision, traceability, and reliability of measurement and how variations in these factors might impact various agencies, companies, and governments. Through experimentation, metrologists investigate the relationships among these factors, whereas theorizing tackles understanding the ways in which these different variables do or could impact each other. The general study of metrology has 3 distinct fields of focus: 1) legal metrology, 2) applies or industrial metrology, and 3) scientific or fundamental metrology.