Templates are used to describe the common layout of a set of figures for the graphical editor. They contain elements you may know from the .gmfgraph model of the Graphical Modeling Framework (GMF). Developing the templates from scratch is done using Wizards. In general the are three types of templates:
Edges (or connections or links) describe the layout of a line connecting two nodes.
A node represents the objects in you diagram.
A compartment is a special node with child elements in the diagram.