In the Beer Lambert Law (equation 3) the term IT/Io is called transmittance. This form of spectroscopy has a setup similar to the one used for Absorption. Reflectance spectroscopy is the study of light as a function of wavelength that has been reflected or scattered from a solid, liquid, or gas.
Definition of metadata: Data that serves to provide context or additional information about other data. For example, information about the title, subject, author, typeface, enhancements, and size of the data file of a ...
Technical metadata corresponds to internal metadata, and business metadata corresponds to external metadata. Kimball adds a third category, process metadata. On the other hand, NISO distinguishes among three types of metadata: descriptive, structural, and administrative.