introduces a definition
token, or non-terminal symbol
delimits optional items
0 or more repetitions of the previous token
1 or more repetitions of the previous token
The examples files are in a read-only directory and therefore you should compile them inside the IDE (by the Editor command
Compile Buffer or the toolbar button or by choosing
Buffer > Compile
from the context menu), so it does not try to write a fasl file.
If you want to manipulate an example file or compile it on the disk rather than in the IDE, then you need first to copy the file elsewhere (most easily by using the Editor command
Write File or by choosing
File > Save As
from the context menu).
Screenshots in this manual show the KnowledgeWorks tools running on Linux under GTK+ with a particular window manager and theme. So if you use GTK+ with a different window manager or theme, or Motif, you should expect a different appearance from that depicted here.
KnowledgeWorks and Prolog User Guide (Unix version) - 24 Mar 2017