Debug is an abstraction that describes the ability to render a value of type A to a human readable format for debugging purposes.

Debug captures this information in a structured data format called a Repr, or a "representation" of the data. This representation can then be rendered to a human readable format using a Renderer, which knows how to render a representation to a specific human readable format. This two step process preserves information when creating the representation and allows rendering it in different ways. For example, we might want to render it as a simple string representation using the Simple renderer or as valid Scala code that we could paste into a REPL with the Scala renderer.

You can use Repr to create structured representations of your own data types and even implement your own Renderer, for example to render representations to JSON, though in most cases the built in renderers will be all that you need.