DGML

Directed Graph Markup Language (DGML) is an XML-based file format for directed graphs.

Introduction to DGML
Here is what a simple directed graph with three nodes and two links between them looks like

which looks like this:



The complete XSD schema for DGML is available at. DGML not only allows describing nodes and links in a graph, but also annotating those nodes and links with any user defined property and/or category.