Classification is a process related to categorization, the process in which ideas and objects are recognized, differentiated and understood. Classification is the grouping of related facts into classes. It may also refer to:

Business, organizations, and economics

• Classification of customers, for marketing (as in Master data management) or for profitability (e.g. by Activity-based costing)
• Classified information, as in legal or government documentation
• Job classification, as in job analysis
• Standard Industrial Classification, economic activities

Mathematics

• Attribute-value system, a basic knowledge representation framework
• Classification theorems in mathematics
• Mathematical classification, grouping mathematical objects based on a property that all those objects share
• Statistical classification, identifying to which of a set of categories a new observation belongs, on the basis of a training set of data

Media

• Classification (literature), a figure of speech linking a proper noun to a common noun using the or other articles
• Decimal classification, decimal classification systems
• Document classification, a problem in library science, information science and computer science
  • Classified information, sensitive information to which access is restricted by law or regulation to particular classes of people
  • Library classification, a system of coding, assorting and organizing library materials according to their subject
• Image classification in computer vision
• Motion picture rating system, for film classification

Science

• Scientific classification (disambiguation)
  • Biological classification of organisms
  • Chemical classification
  • Medical classification, the process of transforming descriptions of medical diagnoses and procedures into universal medical code numbers
  • Taxonomic classification, also known as classification of species
    • Cladistics, an approach using similarities

Organizations involved in classification

• International Society for Knowledge Organization

Other uses

• An industrial process such as mechanical screening for sorting materials by size, shape, and density, etc.
• Civil service classification, personnel grades in government
• Classification of swords
• Classification of wine
• Classification society, a non-governmental organization that establishes and maintains technical standards for the construction and operation of ships and offshore structures
• Locomotive classification
• Product classification
• Security classification, information to which access is restricted by law or regulation