Scheduling Terminology
This section lists terms and definitions used in project scheduling:
- A task is a subdivision or portion of an activity; it describes the lowest level of the WBS.
- An activity is an element of work performed over a period of time within the project. It is a specific piece of work in the WBS. An activity has a measured beginning and a measured end.
- Starting points and ending points of activities are known as events. An example of an event might be Begin Code Development.
- A milestone is an achievement or a significant event in the project or subproject, such as a major decision or completion of an important activity. It is an activity that has zero duration and zero resources.
- A precedence relationship is a dependency between two activities, or between a project activity and a milestone. For example, when creating a driveway, the concrete must be mixed before it is poured; therefore, the task "Pour Concrete" has a precedence relationship with the task "Mix Concrete."
- The precedence diagramming method (PDM) is a means of constructing a project network diagram using nodes to represent activities and connecting them with arrows to show the dependencies. This method is also referred to as an activity-on-node (AON). It is the method used by most project management software, and it can be done manually or on a computer.
- A project network diagram is any schematic display of the dependencies among project activities.