A graph has finite sets of vertices and edges. Vertices are otherwise referred to as nodes, and two of these are connected by an edge like shown in the above image. A tree has a set of nodes, but not necessarily edges. Instead, it has one specific node called the root: this would be "1" in the above picture. The other nodes branch off into subtrees of the root. These disconnected subtrees in graph theory can be interpreted as sets of data: Tn . As opposed to graphs, trees usually have a sense of visual hierarchy in its presentation. Below show examples of how graphs and trees are used in real life to make a better sense of the two:
