Mathematics

A tool and a file format used to process references in conjunction with LaTeX.

Open source typesetting system for technical and scientific documentation.

Collaborative writing and publishing system developed for LaTeX users.

Links to software and teaching materials, plus information in topical categories ranging from algebra to trigonometry. For K-12 through college.
http://archives.math.utk.edu/

Math resources for K-12 teachers, students, and researchers, with extensive links and the "Ask Dr. Math" web form and archive.
http://mathforum.org/

Source of numerous math reference tables, message board, and selected web sites. Formerly "Dave's Math Tables."
http://www.math2.org/

"Collection of mathematics-related resources ... maintained by the Florida State University Department of Mathematics."
http://www.math.fsu.edu/Virtual/index.php

Eric Weisstein's "comprehensive and interactive mathematics encyclopedia," created by contributors worldwide in association with Wolfram Research.
http://mathworld.wolfram.com/

Automatically answers "the most common problems in algebra, equations and calculus faced by high-school and college students."
http://www.quickmath.com

Data tools and databases from the U.S. Census Bureau.

From the website: "Using maps, charts, reports, and relevant links, Ersys covers over 2600 US cities with detailed information on demographics, environmental factors, economic indicators, housing stats, media (newspaper, television, and radio), schools, transportation, local contacts, and much more!"

Data.census.gov is the new platform to access data and digital content from the U.S. Census Bureau. The vision for data dissemination through data.census.gov is to improve the customer experience by making data available from one centralized place so that data users spend less time searching for data content and more time using it.

A source for data about the U.S., such as demographic and economic data, population, and maps. Get information about the 2020 U.S. Census.

A collection of datasets from various sources collected by Google.

Find polling data from the Pew Charitable Trusts on a range of public policies and civic issues.

More links to sources for datasets and databases compiled by the Cornell University Library.

http://www.ams.org/

http://www.awm-math.org/

http://www.maa.org/

http://nafips.ece.ualberta.ca/

http://www.siam.org/