The website Math Archives: Topics in Mathematics: History of Mathematics is located at the University of Tennessee at Knoxville. It can be found at http://archives.math.utk.edu/topics/history.html.
This website addresses possibly every topic imaginable that is related to the history of mathematics. The alphabetic listing begins with Abacus and goes through Women’s Contributions to Mathematics. Most topics have several other links, which lead to even more links, so the user can easily become diverted. I spent hours following links and forgot where I had started. Be forewarned, however, that several links or sub-links are not active.
One example of a topic with many links is Ethnomathematics on the Web. This topic is divided into three groups, one of which has eight links defined by ethnicity or geography. Each of these has from five to twenty links, many of which have several other links. Another group has three sites listed by social categories (Mathematics and gender, Mathematics and economic class, and Multicultural mathematics). The third group of topics has seven links listed by utility.
The topics are just what they say. For example, the topic “Earliest Known Uses of Some of the Words of Mathematics” is just that. Do not expect definitions. You get the origins of the use of the words.
Some links are interactive, such as one of the links on the abacus and one of those on fractals. While the main topic of this site is history of mathematics, not all links are historical. Some are or lead to current events and activities, such as programs under Women and Mathematics, which is a part of the MAA. Also, be prepared for advertisements in some links, as their ISPs are commercial sites.
Each main topic has an indicator, informing the reader if the topic is suitable for grades K-6, or pre-algebra (K6), grades 7-12 (HS), lower division college mathematics (LD), upper division college mathematics (UD), or graduate and professional mathematics (G-P).
This site has something for everyone, for teachers and students, as well as anyone interested in any topic in the history of mathematics.
Laura Smith, Department of Mathematics, North Carolina Central University