A multiway graph is a graph representing all possible branches of evolution for a system. Each node in the graph represents a possible complete state of the system
at a particular step, while each edge corresponds to the evolution of one state to
another as a result of an updating event. In a causally
invariant system, every branching in the multiway system must ultimately reconverge
For example, the illustration above shows the multiway graph for the evaluation of the Fibonacci number using its standard recursive definition. The path followed
by the Wolfram Language's standard evaluator is delineated in red (Wolfram 2023).