If you create nodes by number, the new nodes are spaced equally from each other and from the end nodes. If you create nodes by distance, the new nodes are spaced equally apart from each other and from the endpoints, using the specified distance as the starting point.
Note:
The actual distance between nodes is D/(N+1), where D is the distance between the selected end nodes and N is the number of nodes added. N is calculated to minimize the difference between the specified distance and the actual distance between all the nodes.