Relationships
Relationships can be difficult. Relationships and their dependencies will provide you with a road map of your project and inevitably affect the duration of it and its resources. Just like any road map, there are multiple directions you can go in to reach your final destination. If you have ever taken a long road trip, you may decide to find the most direct route that will get you there the fastest. The same can be true for sequencing your activities together: finding the shortest distance between multiple points. Many highways diverge and converge with each other, as will project activities. Some will abruptly end, while some will carry on to the final destination.
The goal is to create the main output of a precedence network diagram or activity on node (AON). The precedence network diagram is a visual map (Gantt chart for those using software) of all your activities connected by dependency and relationship. The precedence diagram isn't actually a Gantt chart...