Plain text & Markup

Plain text

Form of data that contains only text with no graphical representation. It is different from formatted text stylized using markup. Plaintext documents on computers are common, especially .txt. After some stylization has been applied (ex. bold, italicized, fonts, color, spread..), it becomes rich text.


Markup language

A language that defines the layout of a document - headings, paragraphs... Unlike programming languages, they cannot be used to calculate. Most famous examples are Markdown and HTML.

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)