markdown

Swift
[a link] (https://github.com/user/repo/blob/branch/other_file.md)
[I'm an inline-style link](https://www.google.com)

[I'm an inline-style link with title](https://www.google.com "Google's Homepage")

[I'm a reference-style link][Arbitrary case-insensitive reference text]

[I'm a relative reference to a repository file](../blob/master/LICENSE)

[You can use numbers for reference-style link definitions][1]

Or leave it empty and use the [link text itself].

URLs and URLs in angle brackets will automatically get turned into links. 
http://www.example.com or <http://www.example.com> and sometimes 
example.com (but not on Github, for example).

Some text to show that the reference links can follow later.

[arbitrary case-insensitive reference text]: https://www.mozilla.org
[1]: http://slashdot.org
[link text itself]: http://www.reddit.com
[Link to Google](https://www.google.com)# tier 1 header
##### tier 5 header
**bold**  or  __bold__
*italic*  or  _italic_

[link to markdown guide](https://www.markdownguide.org/basic-syntax/)

> This is a quote. Quotes are indented and a different colour.

show small bits of code with backticks: `print("hello world")` 

- [x] This is a complete item
- [ ] This is an incomplete item

you can also include html code if you want to be more specific.
For example, this would make a picture with a width of 200:
<img src="drawing.jpg" alt="drawing" width="200"/>Markdown is a lightweight markup language with plain-text-formatting syntax,
created in 2004 by John Gruber and Aaron Swartz.
Markdown is often used for formatting readme files,
for writing messages in online discussion forums, 
and to create rich text using a plain text editor.<p>An <a href="http://example.com">example</a>.</p>

<p><img alt="Image" title="icon" src="Icon-pictures.png" /></p>

<blockquote>
<p>Markdown uses email-style characters for blockquoting.</p>
</blockquote>

<p>Inline <abbr title="Hypertext Markup Language">HTML</abbr> is supported.</p>

Source

Also in Swift: