Description of a Project Network Diagram
A project network diagram consists of a series of project activities arranged in a logical flow. It is the basis for a project schedule and provides a consistent framework for planning, monitoring, and controlling the project. Every work element from the WBS is represented in the network diagram, and only WBS work elements are represented there.
The precedence diagram includes only the elements from the lowest level of the WBS. It does not include rollup activities (1.0, 2.0, and so on.).