• CPC -- Central Product Classification
  Central Product Classification
  The Central Product Classification is a product classification for goods and services promulgated by the United Nations Statistical Commission....
  
  
• HS -- Harmonized Commodity Description and Coding System
• CPA -- Classification of Products by Activity
• SITC -- Standard International Trade Classification
• Trade in Services
  Trade in services
  Trade in Services refers to the sale and delivery of an intangible product, called a service, between a producer and consumer. Trade in services takes place between a producer and consumer that are, in legal terms, based in different countries, or economies, this is called International Trade in...
  
  
• Global Classification
  Global Classification
  Global Classification is the process of classifying products for the purpose of complying with customs authorities, qualifying for free trade agreements and filing entries to customs during the importation or exportation of those products...
  
   and Harmonized Schedule Numbers for customs classification
• UNSPSC
  UNSPSC
  The United Nations Standard Products and Services Code is a taxonomy of products and services for use in eCommerce. It is a five-level hierarchy coded as an 8-digit number.-Governance:...
  
  , the United Nations Standard Products and Services Code

Reference

• United Nations Statistical Commission, "International Family of Economic and Social Classifications", p. 5 PDF