eu/iwb/path_win16 is a SAP Parameter attribute which is used to control Info Workbench: File path for Help on Win16 platforms information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
The parameter specifies the path under which the extended help is stored
for the display on Windows 16 Bit frontends. All languages specified
with the parameter eu/iwb/installed_languages must exist in the
subdirectories of this directory which contain the different language
versions of the help. The names of these subdirectories must consist of
the two-digit language identifier of the relevant version.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.