Directed acyclic graphs appear in many data structures such a changeset graphs in distributed version control systems.
Definitions
A directed acyclic graph is directed graph with no cycles.
Graph - A collection of nodes with links between some pairs called arcs
Directed - A graph for which the arcs have a direction. Paths through the graph can only be used in one direction. If node 'x' links to node 'y', it does not automatically follow that node 'y' links to node 'x'.
Acyclic - A graph for which none of the vertices can be reached through a path starting with itself. A path can never reach the same node twice.
Synonyms
- DAG
- acyclic digraph
Common Uses
All trees can be represented as a directed acyclic graph. (But not all directed acyclic graphs are trees.)