The following are guidelines to help solve any problems you may have using this web site.
If you cannot find the answer you need please send us your question and
we will endeavor to answer it as quickly as possible.
Most of the animations on the site are written in Flash. The exception is the Calculus chapter, where they are written in Java.
Both these require a browser plug in.
A gray box, or nothing at all where the interactive animation should be.
Is the problem on just one computer?
If you are on a local network, say inside a school district, the network often has filters to eliminate undesired content. Some times this filter is configures in such a way that it blocks Flash and/or Java. To check for this, try other computers in the network. If they all act badly, contact the network support department and ask them to correct the filter.
As an additional test, try accessing the site from outside the network - say from home. If that works, then it's a filter problem.
Note: These filters are updated automatically sometimes, so a new update may cause a block that was not there before.
so cannot be documented here. In some browsers it is labelled "Enable scripting".
Are the plug-ins installed?
To run Flash and Java you need software plug-ins to be installed. They are downloaded and installed from the manufacturer's sites: