The MathPlayer MathML Test Suite is a superset of the official W3C MathML 2.0 Test Suite.
The only difference in substance is that there is an additional section of "MathPlayer Specific" tests. Some of those tests illustrate MathPlayer's implementation of the MathML <maction> element. The behavior of the <maction> element is not specified by MathML, and is thus inherently implementation specific. The remaining MathPlayer-specific tests don't differ in substance from the W3C version, but merely display MathPlayer's character support in a more convenient format.
Another difference with the W3C test suite is that the tests here have been optimized for display using MathPlayer with Internet Explorer running under Microsoft Windows. In particular, the tests have been prepared as HTML pages with MathML islands, and the pages are served with MIME type text/html. As a consequence, the test suite will not work correctly if you do not have MathPlayer installed on your system or use browser other than Internet Explorer. To learn more about browser interoperability considerations for pages making use of MathML, please consult Creating MathML Web Pages. To install MathPlayer, or to verify a previous installation, please go to http://www.dessci.com/mathplayer/.
The purpose of the test suite is to demonstrate the adherence of MathPlayer to the MathML 1.0 and 2.0 specifications. It is to be used by those who wish to verify MathPlayer's rendering of MathML. It is not meant to teach MathML to someone unfamiliar with it.
MathPlayer is a freely available product produced by Design Science, Inc. to help the world render mathematical equations as easily as they can display text over the web. We encourage all customers to let us know if they encountered any problems in the software. We also encourage all satisfied customers to contact the makers of their favorite browser and ask them to support MathPlayer.