Heading 1

Atx-style headers use 1-6 hash characters at the start of the line, corresponding to header levels 1-6

Heading 1.1

Heading 1.1.1

Heading 1.1.1.1

Heading 1.1.1.1.1

Heading 2

Setext-style headers can be imported but get exported as Atx-style.

Heading 2.1