The *.rules
files are files with rules used by all the different Jena reasoners.
See the comments in the headers of the files. For example for the owl-fb.rules file it is:
OWL rule set v0.3
This rule set is designed to implement owl(f)lite using the hybrid
rule system (mixture of forward and backward chaining). It differs
from earlier versions by more consistently sticking to instance reasoning
by being design to work with the LP backward engine.
It includes an experimental forward version of the equality reasoning which
not yet scalable.
So b
stands for backward chaining
, f
for forward chaining
, and fb
for a combination of the two.