パブリックドメイン

There are many resources available on the net that are in the public domain, and therefore freely usable without restrictions for Wikipedia content.

There are also many copyrighted resources whose licensing terms are liberal enough that they can generally be used as well. For these, see Wikipedia:Free or semi-free non-Public-Domain information resources and Wikipedia:GNU Free Documentation License resources.

This page is intended as a list of only true public domain resources.

Please don't data dump!

The resources below are valuable, but many are very old, context-dependent, written from biased points of view, and otherwise are not in themselves good encyclopedia articles. The 1911 encyclopedia discussed below is a good example of this - it contains some useful information, but also antiquated writing style and innumerable errors of fact. So please, if you copy material from these sources, make sure you take some time to edit, update, introduce, or otherwise produce a good article out of it rather than just dumping it here verbatim. We don't want Wikipedia to become shovelware.

Hot news: The Creative Commons initiative may become a valuable new resource for Wikipedia authors. The project provides a "wizard" for licensing information under various open content licenses (including the public domain, which is not a license), and also features a directory of these works. Please write more about this here as things develop.

Tools for discovering public domain resources

Here are some web searches which may help discover U.S. Federal Government and other public domain documents. Please note that you must still manually verify that documents are in the public domain. Please note that not all sites in the .gov domain are U.S. federal government sites: some may be U.S. state or other local government sites.

This Google search for '"not copyrighted" site:.gov' finds documents on websites in the .gov domain that contain the text "not copyrighted".
This Google search for '"public domain" site:.gov' finds documents on websites in the .gov domain that contain the text "public domain".

Google searches for exact phrases:

"this document is in the public domain" (estimated 2500+ hits)
"this page is in the public domain" (estimated 1000+ hits)
"this information is in the public domain" (extimated 1000+ hits)
"this text is in the public domain" (estimated 2000+ hits)
"placed in the public domain" (estimated 24000+ hits, but many instances refer to other things)
"www.primarilypublicdomain.org" (find links confirming that a site is Primarily Public Domain)

True Public Domain Resources

These resources are completely free of copyright restrictions, and can therefore be used and modified at will for any Wikipedia page. Some (such as Project Gutenberg texts and the public domain dictionary) are in the public domain either because the author has renounced their copyright or because they are very old and their copyrights have expired. (Care should be taken to bring such texts up to date.)

Keep in mind Wikipedia is not a dictionary, though entries should begin with a good definition.

ENCYCLOPEDIC OR GENERAL RESOURCES

US Government

Most publications of the United States Federal Government. Under the Federal Copyright Act material that is originated by the Federal government is not subject to copyright. In some cases, material may originate with a private contractor which assigns the copyright to the agency. However, material that is generated by the Federal government which doesn't have a notice can be copied. Entries below marked "(US Federal Govt.)" belong to this category. Note this only applies to the *Federal* government. United States state governments can copyright materials.

Dictionaries

Hypertext Webster Gateway A searchable interface to a 1913 public-domain Webster's dictionary, downloadable here: Public Domain Dictionary

Other

Project Gutenberg See in particular The Project Gutenberg Encyclopedia (although only Vol 1 of this seems to be available). Note that not all of the Project Gutenberg text are fully in the public domain. Read the license of the respective texts carefully.
1911 Encyclopedia A scanned version of the 1911 Encyclopedia Britannica. The OCR quality is not very high. Some articles end in the middle and continue on the next page. The writing style is antiquated, and the material contains many factual errors. Anything taken from here needs fact-checking and editing. See Wikipedia:1911 Encyclopedia Britannica for ways of best using this material.
The Household Cyclopedia
The Jewish Encyclopaedia

This website contains the complete contents of the 12-volume Jewish Encyclopedia, which was originally published between 1901-1906. The Jewish Encyclopedia, which recently became part of the public domain, contains over 15,000 articles and illustrations. This online version contains the unedited contents of the original encyclopedia. Since the original work was completed almost 100 years ago, it does not cover a significant portion of modern Jewish History (e.g., the creation of Israel, the Holocaust, etc.). However, it does contain an incredible amount of information that is remarkably relavant today.

We are considering inviting the Internet community to help us update the encyclopedia -- if you are interested in volunteering (as a writer, editor, etc.) please join our Mailing List. By putting this important work on the Internet, we hope to improve the quality of Jewish information available online -- and stimulate new discussion. Therefore, we have sections "Discussion Forums" and "Internet Links" which allow our visitors to converse and identify related websites.

ibiblio.org is a major repository of information, "the public's library and digital archive". All collections on ibiblio are assumed to be in the public domain unless otherwise noted. Check for copyright notices on any material you wish to use.

PHILOSOPHY, MATHEMATICS AND NATURAL SCIENCE

Public domain databases of interests to scientists

Astronomy and astrophysics

(US Federal Govt.) Space Educators' Handbook
(US Federal Govt.) NASA glossary of terms - appears to be in the PD, please check

Biology

(US Federal Govt.) US Forest Service Fire Effects Database Database of current information on a wide variety of tree, shrub, grass, mammal, bird, reptile and amphibian species found largely in North America -- great reference material

Chemistry

Earth science

(US Federal Govt.) USGS Mineral Resources Program - "The Mineral Resources Program provides and communicates current, impartial information on the occurrence, quality, quantity, and availability of mineral resources."
(US Federal Govt.) NASA GISS glossary of climate terms
(US Federal Govt.) NASA Earth Observatory Glossary

Mathematics

biographies of mathematicians - from a 1908 history of mathematics. See the discussion at Rouse History of Mathematics

Philosophy

Physics

Relativity: The Special and General Theory by Albert Einstein
Physics for Free has two public domain physics books by a Yale professor: one about basic physics, one about groups and particles.

Statistics

SOCIAL SCIENCES

Anthropology

Archaeology

Economics

Geography

(US Federal Govt.) U.S. Census Bureau Has an enormous range of facts and figures which we will find helpful in fleshing out articles about cities and states.
(US Federal Govt.) Summary Demographic Data by Country from the US Census Bureau
(US Federal Govt.) CIA World Factbook Contains basic facts on all the countries of the world.
(US Federal Govt.) U.S. State Dept.: Background notes on the countries of the world. Also see their copyright notice, which, as you'll see, places material that is not explicitly copyrighted in the public domain.
(US Federal Govt.) the NIMA www.nima.mil GEOnet Names Server contains approximately 3.88 million named geographical features outside the United States, with 5.34 million names
(US Federal Govt.) the USGS Geographic Names Information System claims to have almost 2 million physical and cultural geographic features within the United States

History

History of science and technology

Language and Linguistics

Political science

(US Federal Govt.) Library of Congress Country Studies information on 101 countries, including detailed histories.

Psychology

APPLIED ARTS AND SCIENCES

Agriculture

Architecture

Business and industry

(US Federal Govt.) US Energy Information Agency - statistics and info on energy industry (mostly US but some stuff for the world) - they appreciate but do not require acknowledgement (copyright info here)

Communication

(US Federal Govt.) Federal Standard 1037C, a telecommunications glossary, appears to be mostly in the public domain based on these principles, and is a source of a large number of bits of useful material. A few items are derived from copyrighted sources: where this is the case, there is an attribution to the source. Note: a substantial number of non-trivial 1037C articles are now incorporated into Wikipedia -- please note that only those articles that have substantial content and are from 100% public domain sources are appropriate to be used in the Wikipedia
(US Federal Govt.) DISA site about commercial telecommunications standards From the site: "This site is maintained by the Commercial Standards Division of the Defense Information Systems Agency (DISA) to provide information about the current status of commercial telecommunications standards."

Computer science

(US Federal Govt.) NIST Dictionary of Algorithms, Data Structures, and Problems: Huge, high-quality resource. All entries are in the public domain except for a few that carry an explicit copyright notice.
Public domain lecture notes: "Introduction to Computer Science", "Data Structures" and "Analysis of Algorithms"
The Jargon File Eric S. Raymond's definitive work on geek-speak.

Education

Employment

(US Federal Govt.) Occupational Outlook Handbook Contains descriptions of a great many occupations such as Physical Therapist.

Engineering

Law

Medicine

(US Federal Govt.) Medline at the NIH copyright terms here indicating materials in public domain unless indicated otherwise
(US Federal Govt.) NIH public domain publications on urology
(US Federal Govt.) NIMH Patient education materials (Public Domain)
(US Federal Govt.) USDA Nutrient Data Laboratory Contains nutritional information on loads of foods. (From FAQ), "USDA food composition data is in the public domain and there is no copyright. We would appreciate it if you would list us as the source of the data and when possible we would like to see the product which uses the data or be notified of its use."
(US Federal Govt.) A large collection of public domain information sheets on various neurological disorders
- Note: This Google search for "nih publication "not copyrighted" site:.gov" should help uncover more NIH public domain documents
University of Cincinnati etexts: Contains a nice edition of 1918 Gray's Anatomy with illustrations.
(US Federal Govt.) U.S. National Toxicology Program: copyright notice here, typical U.S. govt terms.
The Bad Bug Book at http://www.cfsan.fda.gov/~mow/intro.html appears to be in the public domain: but please check each section individually for public domain status.
Asthma genetics - Public domain data

Military

(US Federal Govt.) U.S. Navy, Info on specific ships
(US Federal Govt.) Air Force Link

Public affairs

(US Federal Govt.) Federal Emergency Management Agency: Not sure how much of this is useful, but anyway it's under the same terms as the U.S. Department of State site: all in the public domain unless it carries an explicit copyright notice.
(US Federal Govt.) U.S. Environmental Protection Agency: copyright notice here, typical U.S. gov't terms. Does have some good information for people patient enough to find it.
(US Federal Govt.) Voice Of America - All text, audio and video material produced exclusively by the Voice of America is public domain. However, some images and graphics are licensed for use and covered by all applicable copyright laws.

Technology

Transport

CULTURE

UNESCO Public Domain Resources and Virtual Library at this URL

Arts and Entertainment

Classics

Cooking

Libraries

Online Book Initiative
Public Domain Reader: Public domain works in HTML, PDF and Plain_text formats.
The Online Books Page: A comprehensive index of books available on the Internet. Most are public domain, but not all; check for copyright restrictions.
Public Book Shelf

Literature

Music

The Choral Public Domain Library describes itself as 'A Free Sheet Music Archive'
Mutopia: a collection of public domain sheet music.
Project Gutenberg music section

Recreation

Religion

Biblical dictionaries: Some late nineteenth century Biblical dictionaries; these might need work to render unbiased and up to date.
- A number of articles already contain most of the useful text from Easton's Bible Dictionary (1897)
- Hitchcock's Bible Dictionary's list of Biblical names has been used as a source for the List of Biblical names.
- Smith's Bible Dictionary is another 19th century Bible dictionary, with much useful but dated text
Public Domain Biblical references
Christian Classics Ethereal Library: A project similar to Project Gutenberg, but focusing on Christian texts.

Sports

MISCELLANEOUS

Writings by Greg Goebel: Science, technology, military history, introductions to classical and relativistic physics.
Infoanarchy: a weblog dedicated to copyright issues. All original material is in the public domain, although some redistributed articles may be under copyright.

TO BE FILED

please file these resources under the appropriate topic headings above

There are no more entries to be filed at the moment

Public Domain Images

Please see the new article Public domain image resources.

Sources for finding public domain resources

Book:

The Public Domain: How to Find & Use Copyright-Free Writings, Music, Art & More by Stephen Fishman, ISBN 0873374339

Lists of general resources:

Registry for material that is in the public domain "except as noted"
Links to websites "mostly" in the public domain maintained by Minciu Sodas
Unmaintained list of public domain resources by Kevin Savetz
Banis Associates list of public domain resources
Public Domain Music website
Brian Waters' list of public domain resources
New General Catalog of Old Books and Authors tracking old books and author's dates for determining copyright expiration

Lists of U.S. Government resources: