Terminators are simply the symbols at the end of paths that show direction and add meaning to the relationship represented by the path. Arrowheads are the most common example. Built-in path styles have pre-defined terminators based on the diagram type. However, you have full control to change them as you see fit.

A collection of the most common terminators for the current diagram is always available by right-clicking on the end of a path. Plus, you can load additional terminators from the Terminator Gallery that stores an even wider selection organized by category.