PPWIZARD is a free preprocessor for HTML, REXX, Visual Basic or any text files.
This variable will be replaced by a '$' character. You may need to use it in some situations, for example, where you wish to generate '<$' (otherwise PPWIZARD will interpret this as the start of macro replacement).
This symbol actually expands to a <?xXX> code and not the '$' character directly. In some cases this may not be what you wish and you should either define your own alternative or use some other method (#define may be suitable in a lot of cases), depending on your need.
This is a Standard Definition which always exists (you don't need to #define it). Note that you can create your own variations or completely new ones (see the examples).