> [!tldr] **Directed Acyclic Graph** is a type of [[Graph]] which is directed, and there is no *cycles* in the graph. This makes the graph useful in representing all sorts of things. "Directed Acyclic Graph" (DAG) sounds fancy and hifalutin - but it just means a series of things that point at other things, where there are no loops. ![[DAG 2026-09-13 10.57.09.excalidraw.svg]] %%[[DAG 2026-09-13 10.57.09.excalidraw.md|🖋 Edit in Excalidraw]]%% A [[Hierarchy|tree]] is one form of DAG. So is a *backwards* tree (where a bunch of branches point toward the trunk). A tree with all sorts of knots in it, so long as the knots doing point *backwards*, is also a DAG. ![[DAG 2026-09-13 11.00.58.excalidraw.svg]] %%[[DAG 2026-09-13 11.00.58.excalidraw.md|🖋 Edit in Excalidraw]]%% Algorithms that work on DAGs can be used across a wide variety of purposes. ## Usefulness - DAGs can be used to express [[5 Whys|Cause and Effect Chains]] - ...which is everything that occurs in time. - DAGs are used in representing workflows in workflow orchestrators. **** # More ## Source - Wikipedia ## Related - [[Graph Theory]]