Both terms are used to determine the complexity of code. It’s always good to keep your code simple and readable as referred in KISS principle.
Complexity is determined by the number of decision points in a method plus one for the method entry. The decision points are ‘if’, ‘while’, ‘for’, and ‘case labels’. Generally, 1-4 is low complexity, 5-7 indicates moderate complexity, 8-10 is high complexity, and 11+ is very high complexity.
The NPath complexity of a method is the number of acyclic execution paths through that method.