An arrow diagramming method (ADM) is a network diagramming technique in which activities are represented by arrows.[1]
It is used for scheduling activities in a project plan.
The precedence relation between activities is represented by circles connecting to one or more arrows. The length of the arrow represents the duration of the relevant activity.
Sometimes a "dummy task" is added, to represent a dependency between tasks, which does not represent any activity.
Use of the ADM as a common project management practice has declined with the adoption of computer-based scheduling tools. The precedence diagram method (PDM) is often favored over the ADM.
The ADM is also known as the activity-on-arrow (AOA) method, it only show finish-to-start relationship.
ADM network drawing technique the start and end of each node or event is connected to an arrow.
The start of the arrow comes out of a node while the tip of the arrow goes into a node. Between the two nodes lies an arrow that represents the activity.
The event represented by the circular node consumes neither time nor resources.