Number of nodes
If G is the graph under consideration, this number is usually noted with n (G) (or n for short , if it is clear which graph it is). Alternatively, you can also write | G |. If the set / number of nodes is finite, one speaks of finite graphs, otherwise of infinite graphs.
Graph theory differentiates between nodes (also called corners) and edges. The nodes usually designate events, while the connections connecting them represent processes or activities. If the edges are given by pairs of nodes instead of sets, we speak of directed graphs. In this case a distinction is made between the edge (a, b) - as the edge from node a to node b - and the edge (b, a) - as the edge from node b to node a.