Directed Acyclic Graph (DAG)
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An acyclic graph has a direction, as well as a lack of cycles. It is used to model probabilities, connectivity, and causality. A directed acyclic graph DAG consists of vertices and edges (also called arcs), with each edge directed from one vertex to another, such that following those directions will never form a closed loop. There can be multiple paths in the flow, which means it recognizes the need to process data in multiple ways to accommodate different outputs and needs.
There are four characteristics: nodes (a place to store data), directed edges (arrows pointing in one direction), some great ancestral node with no parents, and leaves (nodes with no children). The data structure of a directed acyclic graph is different as it has no directed edges, and it also has a topological ordering. This means that the nodes are ordered so that the starting node has a lower value than the ending node.