md export back-end generates Markdown syntax1 for an Org
It is built over HTML back-end: any construct not supported by Markdown
syntax (e.g., tables) will be controlled and translated by
back-end (see HTML export).
Markdown export can generate both
setext types for
headlines, according to
org-md-headline-style. The former introduces
a hard limit of two levels, whereas the latter pushes it to six. Headlines
below that limit are exported as lists. You can also set a soft limit before
that one (see Export settings).