Figure 1.

All the connected graphs on up to five nodes. When appearing as an induced subgraph of a larger graph, we call them graphlets. They contain 73 topologically unique node types, called ‘automorphism orbits’. In a particular graphlet, nodes belonging to the same orbit are of the same shade. Graphlet G₀ is just an edge, and the degree of a node historically defines how many edges it touches. We generalize the degree to a 73-component ‘graphlet degree’ vector that counts how many times a node is touched by each particular automorphism orbit. This figure is adapted from Pržulj (2007).