section_path: Collection and classification
section_name: Collection and classification
paragraph_text: Collection and classification
  
  Personal and public libraries, archives and other forms of book collection have led to the creation of many different organization and classification strategies. In the 19th and 20th century, libraries and library professionals systematized book collecting and classification systems to respond to the growing industry. The most widely used system is ISBN, which has provided unique identifiers for books since 1970.