  Programming in Prolog is hard for programmers that are used to procedural
coding. In this manual the method of drawing search trees is introduced with
the aim to get a better understanding of how Prolog works. After giving a first
example of a Prolog database, query and search tree, the art of drawing search
trees is systematically introduced giving guidelines for queries with
variables, conjunction, disjunction, and negation. Further examples are
provided by giving the complete search trees that are shown in Learn Prolog
Now!
