Markdown syntax guide and writing on Markdown
Markdown is intended to be as easy-to-read and easy-to-write as is feasible.
Readability, however, is emphasized above all else. A Markdown-formatted document should be publishable as-is, as plain text, without looking like it's been marked up with tags or formatting instructions.
Markdown's syntax is intended for one purpose: to be used as a format for writing for the web.