RIF is part of the infrastructure for the semantic web, along with (principally) SPARQL, RDF and OWL.
The working group started with more than 50 members and two chairs drawn from industry, Christian de Sainte Marie of ILOG, and Chris Welty of IBM.
The charter, to develop an interchange format between existing rule systems was influenced by a workshop in the spring of 2005 in which it was clear that one rule language would not serve the needs of all interested parties (Dr. Welty described the outcome of the workshop as Nash Equilibrium[3]).
Rules are a simple way of encoding knowledge, and are a drastic simplification of first order logic, for which it is relatively easy to implement inference engines that can process the conditions and draw the right conclusions.
RIF BLD corresponds to positive datalogs, that is, logic programs without functions or negations.
The PRD specification defines one such resolution strategy based on forward chaining reasoning.
Example: The Uncertainty Rule Dialect (URD)[12] supports a direct representation of uncertain knowledge.
RIF-SILK also includes a number of other features present in more sophisticated declarative logic programming languages such as SILK.