parent node

A node connected to the current node that is closer to the root node. In a tree, all links incident to a parent node end at child nodes, except one that ends at the parent node's parent node.

path

A sequence of consecutive nodes leading from one node to another using the links of the graph. It is the route along the links through the nodes in a graph. The length of a path is the number of links traversed.

planar graph

A graph that can be drawn with no links crossing other links.

polyline drawing

A drawing where each link is drawn as a polygonal chain.

preferred layout

In the context of Recursive Layout, the layout instance set as the one to be used for each graph. It is stored in a property of the graph.