Measurement in science is the process of obtaining the magnitude of a quantity relative to an agreed standard. It is fundamental to the sciences, engineering, construction, and other technical fields. In science, a measurement is a collection of quantitative or numerical data that describes a property of an object or event. The science of weights and measures is called metrology.

The process of measurement begins with a definition of the quantity that is to be measured, and it always involves a comparison with some known quantity of the same kind. If the object or quantity to be measured is not accessible for direct comparison, it is converted or “transduced” into an analogous measurement signal.

Measurement theory is the study of how numbers are assigned to objects and phenomena, and its concerns include the kinds of things that can be measured, how different measures relate to each other, and the problem of error in the measurement process. Any general theory of measurement must come to grips with three basic problems: error; representation, which is the justification of number assignment; and the relationship between empirical and theoretical structures.

The dimensions of the different types of matter measured in scientific research vary a lot, and to keep measurements in a usable scale, scientists use SI prefixes, which are multipliers that change unit values by multiples of ten. Precision is the degree of reproducibility of a measured quantity; how close a series of measurements of the same quantity are to one other.

In summary, measurement in science is the process of obtaining numerical data that describes a property of an object or event, and it involves a comparison with some known quantity of the same kind. It is fundamental to the sciences, engineering, construction, and other technical fields, and it requires precision and accuracy to be useful.