MathWorld

MathWorld is an online mathematics reference work, sponsored by Wolfram Research Inc., the creators of the Mathematica computer algebra system. It is also partially funded by the National Science Foundation's National Science Digital Library grant to the University of Illinois at Urbana-Champaign.

History
Eric W. Weisstein, the creator of the site, was a physics and astronomy student who got into the habit of writing notes on his mathematical readings. In 1995 he put his notes online and called it "Eric's Treasure Trove of Mathematics"; it contained hundreds of pages/articles, covering a wide range of mathematical topics. The site became popular as an extensive single resource on mathematics on the web. Weisstein continuously improved the notes and accepted corrections and comments from online readers. In 1998, he made a contract with CRC Press and the contents of the site were published in print and CD-ROM, titled "CRC Concise Encyclopedia of Mathematics". The free online version became only partially accessible to the public. In 1999 Weisstein went to work for Wolfram Research, Inc. (WRI), and WRI renamed the Math Treasure Trove to MathWorld at http://mathworld.wolfram.com and hosted it on the company's website without access restrictions.

CRC lawsuit
In 2000, CRC Press sued WRI, WRI president Stephen Wolfram, and author Eric Weisstein, due to what they considered a breach of contract: that the MathWorld content was to remain in print only. The site was taken down by a court injunction. The case was later settled out of court, with WRI paying an unspecified amount and complying with other stipulations. Among these stipulations is the inclusion of a copyright notice at the bottom of the website and broad rights for the CRC Press to produce MathWorld in printed book form. The site then became once again available free to the public.

This case made a wave of headlines in online publishing circles. The PlanetMath project was a result of MathWorld being unavailable.

Criticism
On the Usenet group sci.math, there have been comments on the quality of MathWorld's articles. While the information in MathWorld is considered generally correct, there have been incorrect statements and typos in MathWorld articles. Mathworld has a facility that allows readers to submit comments on individual articles. There is no known systematic study of MathWorld's consistency, nor that of other on-line math resources, including Wikipedia, so their quality remains a matter of debate and discussion.