classifications
A classification is a division or category in a system which divides things into groups or types.
The government uses a classification system that includes both race and ethnicity.
政府采用一种既包括人种又包括种族的类别体系。
The classification of things is the act of dividing them into groups or types so that things with similar characteristics are in the same group.
the arbitrary classification of knowledge into fields of study.
主观地将知识归入研究领域的分类。
the British Board of Film Classification.
英国电影分级委员会。