The classpath is the list of places that Java looks to find
the bits of compiled code that it uses to run an application.
Depending on how you have done your installation the core STILTS
classes could be in various places, but they are probably in a
file with one of the names
stilts.jar,
topcat-full.jar or
topcat-extra.jar.
The full pathname of one of these files can therefore be used as
your classpath. In some cases these files are self-contained and
in some cases they reference other jar files in the filesystem -
this means that they may or may not continue to work if you
move them from their original location.
Under certain circumstances the tools might need additional classes, for instance: