All HTML rendered in OpenCms is rendered via JSPs. Thus, also the HTML that displays content is rendered via JSPs. A JSP that renders content is called a formatter. A formatter is configured via a formatter configuration. The configuration specifies which content of which type is rendered with which formatter in which containers.
In addition to information about where to use a formatter, the configuration can contain information about special settings available for the formatter. These are called element settings.
When you use the "Add resource type" wizard of the module administration, an example formatter and formatter configuration are generated automatically. Using this wizard is the best option if you create a new content type that is exposed as a resource type.