General Reference

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The National Library of Medicine (NLM), on the campus of the National Institutes of Health in Bethesda, Maryland, is the world's largest medical library. The Library collects materials and provides information and research services in all areas of biomedicine and health care.

Welcome to MedlinePlus, a goldmine of good health information from the world's largest medical library, the National Library of Medicine. Health professionals and consumers alike can depend on it for information that is authoritative and up to date. MedlinePlus has extensive information from the National Institutes of Health and other trusted sources on over 650 diseases and conditions. There are also lists of hospitals and physicians, a medical encyclopedia and a medical dictionary, health information in Spanish, extensive information on prescription and nonprescription drugs, health information from the media, and links to thousands of clinical trials. MedlinePlus is updated daily and can be bookmarked at the URL: medlineplus.gov. There is no advertising on this site, nor does MedlinePlus endorse any company or product.

At this site you will find over 500 databases and Web sites containing information and resources pertaining to science and technology of interest to the Department of Energy, with an emphasis on the physical sciences. Sponsored, developed, and maintained by the Department of Energy's Office of Scientific and Technical Information (OSTI), EnergyFiles combines information, tools, and technologies to facilitate access to and use of scientific resources.

Search and browsw the library. Mathmatics topics: Algebra, Analysis, Arithmetic/Early Math, Calculus (Single Variable), Calculus (Multivariable), Communicating Math, Differential Equations, Discrete Math, Dynamical Systems (Chaos, Fractals...), Geometry, History and Biography, Logic/Foundations, Number Theory, Numerical Analysis, Operations Research, Pre-Calculus (Functions, Inequalities, Trigonometry), Probability/Statistics, Topology, Applications/Connections. Educational materials. Teaching issues/strategies.

Science.gov is a gateway to authoritative selected science information provided by U.S. Government agencies, including research and development results. Agriculture & Food Food Safety, Gardening, Pesticides, Veterinary Science Applied Science & Technologies Biotechnology, Electronics, Engineering, Transport Astronomy & Space Exploration, Planets, Space Technologies Biology & Nature Animals & Plants, Ecology, Genetics, Pest Control Computers & Communication Networks, Hardware, Software Earth & Ocean Sciences Land, Maps, Natural Disasters, Oceans, Weather Energy & Energy Conservation Energy Use, Fossil Fuel, Solar, Wind Environment & Environmental Quality Air/Water/Noise Quality, Cleanup, Climate Change Health & Medicine Disease, Health Care, Nutrition, Mental Health Math, Physics, & Chemistry Astrophysics, Chemicals, Mathematical Modeling Natural Resources & Conservation Ecosystems, Energy Resources, Forest Science, Mining Science Education Homework Help, Teaching Aids, Science Internships

The National Academies Press (NAP) was created by the National Academies to publish the reports issued by the National Academy of Sciences, the National Academy of Engineering, the Institute of Medicine, and the National Research Council, all operating under a charter granted by the Congress of the United States. NAP publishes over 200 books a year on a wide range of topics in science, engineering, and health, capturing the most authoritative views on important issues in science and health policy. The institutions represented by NAP are unique in that they attract the nation's leading experts in every field to serve on their blue ribbon panels and committees. For definitive information on everything from space science to animal nutrition, you have come to the right place. Read more than 3,000 books online for FREE! New Releases. Ordering info.

Founded in 1901, NIST is a non-regulatory federal agency within the U.S. Commerce Department's Technology Administration. NIST's mission is to develop and promote measurement, standards, and technology to enhance productivity, facilitate trade, and improve the quality of life.

Information at the foundation of modern science and technology from the Physics Laboratory of the National Insitute of Standards and Technology (http://www.nist.gov/). Constants include: universal, electromagnetic, atomic and nuclear, physico-chemical, adopted values, non-SI units, conversion factors for energy equivalents, X-ray values, frequently used constants, extensive listings. Find the correlation coefficient between any pair of constants.

National Science Digital Library. NSF's online library of resources for science, technology, engineering and mathematics education.

About copyright. Copyright basics. Frequently asked questions. Current fees. Search copyright records. Publications. Licensing. How to register a work. How to record a document. Law and policy. Copyright law. Federal register notices. Current legislation. Regularions. Mandatory deposit. Patents and Trademarks. Freedom of Information Act.

United States Central Intelligence Agency. About the CIA. CIA careers. Press room. Library and reference. Federal government links. Director of Central Intelligence. Central Intelligence Agency. CIA's Homepage for Kids.

PubMed, a service of the National Library of Medicine, includes over 15 million citations for biomedical articles back to the 1950's. These citations are from MEDLINE and additional life science journals. PubMed includes links to many sites providing full text articles and other related resources.

The U.S. Department of Energy's (DOE) Office of Scientific and Technical Information (OSTI) provides access to a wealth of energy, science, and technology research and development (R&D) information from the Manhattan Project to the present.