Arbology: Trees and pushdown automata

Abstract

Trees are (data) structures used in many areas of human activity. Tree as the formal notion has been introduced in the theory of graphs. Nevertheless, trees have been used a long time before the foundation of the graph theory. An example is the notion of a genealogical tree. The area of family relationships was an origin of some terminology in the area of the tree theory (parent, child, sibling, ...) in addition to the terms originating from the area of the dendrology (root, branch, leaf, ...). © 2010 Springer-Verlag Berlin Heidelberg.