Parallel Logic Languages
There are two major forms of parallelism in logic programs are:
AND parallelism and OR parallelism.
OR parallelism means the parallel evaluation of several clauses whose head unifies with the goal.
If we have the subgoal ?p(X) and the clauses:
p(X) :- q(X). p(X) :- r(X). p(X) :- s(X).
OR parallelism is exploited by unifying in parallel the subgoal with the head of the three clauses.
AND parallelism consists of the parallel evaluation of each subgoal that composes the current goal. If the goal to be solved is
using AND-parallelism, subgoals p(X) and q(Y) are solved in parallel.