Markdown

Markdown is a markup language. It is the de facto (unofficial) standard for writing READMEs for programs, and many programs can convert markdown documents into richtext.

# Heading 1
## Heading 2
### Heading 3

Alternative heading 1
=====================

Alternative heading 2
---------------------

**bold**, *italicized*

> blockquote

1. List item
2. List item
3. List item

- List item
- List item

`code`

--- - horizontal rule

[Link](http://a.com)

[Image](http://a.com/image.png)

or

[Image](image.png)

Commonmark.org (full specification)