available drawing features
The embedded tool of choice for Confluence Scribbles is SVG-Edit - A complete vector graphics editor in the browser
You can read their documentation for the full power, but below are some common activities.
Freehand drawing uses paths, lines, and shapes
You can use the pointer tool to move, highlight, or clone existing shapes.
Advanced Process Flow / Diagramming Shapes
SVG-Edit also has a collection of pre-defined shapes helpful for diagramming activities.