Reference Sources

The US government profiles of countries and territories around the world. Information on geography, people, government, transportation, economy, communications and more.
The Free Dictionary is a comprehensive general English dictionary by Houghton Mifflin's premier dictionary, the American Heritage® Dictionary of English Language augmented with Collins English Dictionary – Complete and Unabridged, and is enhanced by illustrations, an audio pronunciation feature, etymologies, abbreviations, biographical entries, and more. It incorporates medical, legal and financial dictionaries with encyclopedia.
Encyclopædia Britannica, Inc., is a global educational publisher with products that promote knowledge and learning. It provides timely, relevant, and trustworthy information and instructional products used in schools, universities, homes, libraries, and workplaces throughout the world. has more than 100 trusted sources, including encyclopedias, dictionaries, and thesauruses with facts, definitions, biographies, synonyms, pronunciation keys, word origins, and abbreviations.
The A.D.A.M. Medical Encyclopedia includes over 4,000 articles about diseases, tests, symptoms, injuries, and surgeries. It also contains an extensive library of medical photographs and illustrations
The World Almanac and Book of Facts is a reputable American reference book of all time. This essential household and workplace desk reference is “the most useful reference book known to modern man,” according to the L.A. Times.
Provides annotated links to resources on standards, citing and evaluating Web sites, and understanding copyright and fair use laws as they apply to the use and creation of educational materials on the Web." History Matters is "designed for high school and college teachers of U.S. History courses" and was developed at City University of New York and George Mason University.
The World Bank's Open Data initiative is intended to provide all users with access to World Bank data. The data catalog is a listing of available World Bank datasets, including databases, pre-formatted tables and reports.  
The Wordweb free edition is a one-click English thesaurus and dictionary for Windows, which can work online and off-line. The program can look up words in almost any program and then provide a definition, pronunciation, related words, and list of synonyms. The dictionary includes over 150,000 root words and 120,000 synonym sets and covers American, British, Canadian, Australian, Indian, and global English. This version is compatible with computers running Windows 98 and newer.
The search engine list is a comprehensive list of search engines on the internet.
The Guinness Book of Records - later renamed Guinness World Records provides access to to world records with regards to knowing the extremes - the biggest, the smallest, the fastest, the most and the least - offers a way of comprehending and digesting an increasingly complex world overloaded with information.It has become ayardstick for measuring how you and those around you fit  to these records of extremes.