DOT is not only a punctuation mark, it is also a graph description language used by Graphviz - an open source software for graph visualization. Graphviz is very helpful when one needs to display any object with connections, be they physical or logical, such as networks and flowcharts.
Since I am currently going through simulation algorithms, it is really handy to have that diagram displaying relationships between various probability distributions in front of me. Here I can mark quickly which algorithms I have already implemented and which not. The diagram was created with the DiagrammeR package with the code presented below.