contents/Reference

• Books – a book is a set of written, printed, illustrated sheets, made of ink, paper, parchment, or other materials, usually fastened together to hinge at one side. Books are used to convey knowledge and other information.
  • Great books listed in How to Read a Book
  • Great Books of the Western World
  • Harvard Classics
• General subject outlines (trees of knowledge)
  • Taxonomies (trees) of knowledge included within larger works
    • Figurative system of human knowledge (from the Encyclopédie)
    • Outline of academic disciplines
    • Outline of Knowledge (part of the Propædia of the 15th edition of Encyclopædia Britannica)
    • Outline of the knowledge of humanity
  • Subject classification systems
    • Academic classification systems
      • Fields of doctoral studies (United States)
      • Joint Academic Classification of Subjects
    • Library classification systems
      • Bliss bibliographic classification
      • Colon classification
      • Cutter Expansive Classification
      • New Classification Scheme for Chinese Libraries
      • Dewey Decimal classes
      • Library of Congress Classification
      • Universal Decimal Classification
• Knowledge – familiarity, awareness or understanding of someone or something, such as facts, information, descriptions, or skills, which is acquired through experience or education by perceiving, discovering, or learning. Knowledge can refer to a theoretical or practical understanding of a subject. It can be implicit (as with practical skill or expertise) or explicit (as with the theoretical understanding of a subject); it can be more or less formal or systematic.
• Wiki – free-access, free content Internet encyclopedia, supported and hosted by the non-profit Wiki Foundation. Anyone who can access the site can edit almost any of its articles. Wikipedia is the sixth-most visited website and constitutes the Internet's largest and most popular general reference work.

General reference lists  • Abbreviations • Collective nouns • Common misconceptions • Common misspellings • Etymologies • Lists • Lists of lists • List of lists of lists • Pairs • Postal codes • Unusual articles

Reference of organizations 

Libraries • Types of libraries • Digital library projects • National libraries

Reference works • Almanacs • Dictionaries • Encyclopedias • Free online journals • Newsgroups • Newspapers • Web directories

Research tools and resources • Free software programs • IRC clients • News clients • Periodic table • Search engines

Standards • Common standards • Numbering schemes

International standards • List of International Organization for Standardization standards • ISO 639 language names • ISO 3166 country codes • Time zones • Country calling codes • Internet TLDs • Plastic recycling codes
United States standards • Federal Standard 1037C (Glossary of telecommunication terms) • FIPS country codes • U.S. postal abbreviations
Size, measurement and conversions
SI • SI base units • SI derived units • SI prefix
Unit conversions • Unusual units of measurement • Humorous units of measurement
Orders of magnitude • Length • Area • Volume • Mass • Time
Specific measures • Cooking • Ancient • Paper sizes

See: Lists of topics: Reference

• "-graphies" (subjects ending in "graphy").
• Library and information science

Main categories: Research and Library science

See: Overviews: Reference and Lists of topics: Reference

Standards