short url: caseywatts.com/graphviz
Graphviz is like markdown, for diagrams.
It's a tool that can transform text input into a "directed graph" output, which is nodes pointing to other nodes. You can use it for architecture diagrams, DB diagrams, documentation for users, etc.
You'll want to use a tool with a two-pane layout - the left side is the source text, the right side is the image output.
- For just you working on it, use http://graphviz.it (shown above; it has more features)