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writing/Markdown
# Markdown Cheatsheet

Forked from [here](https://github.com/adam-p/markdown-here/wiki/Markdown-Cheatsheet).

- [Headers](#headers)
- [Emphasis](#emphasis)
- [Lists](#lists)
- [Links](#links)
- [Images](#images)
- [Code and Syntax Highlighting](#code)
- [Tables](#tables)
- [Footnotes](#footnotes)
- [Blockquotes](#blockquotes)
- [Inline HTML](#html)
- [Horizontal Rule](#hr)
- [Line Breaks](#lines)
- [Escaping Control Characters](#escape)
- [Youtube videos](#videos)

---

## Headers

```no-highlight
# H1
## H2
### H3
#### H4
##### H5
###### H6

Alternatively, for H1 and H2, an underline-ish style:

Alt-H1
======

Alt-H2
------
```

# H1
## H2
### H3
#### H4
##### H5
###### H6

Alternatively, for H1 and H2, an underline-ish style:

Alt-H1
======

Alt-H2
------

----

## Emphasis

```no-highlight
Emphasis, aka italics, with *asterisks* or _underscores_.

Strong emphasis, aka bold, with **asterisks** or __underscores__.

Combined emphasis with **asterisks and _underscores_**.

Strikethrough uses two tildes. ~~Scratch this.~~
```

Emphasis, aka italics, with *asterisks* or _underscores_.rr

Strong emphasis, aka bold, with **asterisks** or __underscores__.

Combined emphasis with **asterisks and _underscores_**.

Strikethrough uses two tildes. ~~Scratch this.~~


---

## Lists

(In this example, leading and trailing spaces are shown with with dots: ⋅)

```no-highlight
1. First ordered list item
2. Another item
⋅⋅* Unordered sub-list.
1. Actual numbers don't matter, just that it's a number
⋅⋅1. Ordered sub-list
4. And another item.

⋅⋅⋅You can have properly indented paragraphs within list items. Notice the blank line above, and the leading spaces (at least one, but we'll use three here to also align the raw Markdown).

⋅⋅⋅To have a line break without a paragraph, you will need to use two trailing spaces.⋅⋅
⋅⋅⋅Note that this line is separate, but within the same paragraph.⋅⋅
⋅⋅⋅(This is contrary to the typical GFM line break behaviour, where trailing spaces are not required.)

* Unordered list can use asterisks
- Or minuses
+ Or pluses
```

1. First ordered list item
2. Another item
* Unordered sub-list.
1. Actual numbers don't matter, just that it's a number
1. Ordered sub-list
4. And another item.

You can have properly indented paragraphs within list items. Notice the blank line above, and the leading spaces (at least one, but we'll use three here to also align the raw Markdown).

To have a line break without a paragraph, you will need to use two trailing spaces.
Note that this line is separate, but within the same paragraph.
(This is contrary to the typical GFM line break behaviour, where trailing spaces are not required.)

* Unordered list can use asterisks
- Or minuses
+ Or pluses

---

## Links

There are two ways to create links.

```no-highlight
[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]

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
```

[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]

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

---

## Images

```no-highlight
Here's a logo (hover to see the title text):

Inline-style:
![alt text](https://github.com/adam-p/markdown-here/raw/master/src/common/images/icon48.png "Logo Title Text 1")

Reference-style:
![alt text][logo]

[logo]: https://github.com/adam-p/markdown-here/raw/master/src/common/images/icon48.png "Logo Title Text 2"

```

Here's a logo (hover to see the title text):

Inline-style:
![alt text](https://github.com/adam-p/markdown-here/raw/master/src/common/images/icon48.png "Logo Title Text 1")

Reference-style:
![alt text][logo]

[logo]: https://github.com/adam-p/markdown-here/raw/master/src/common/images/icon48.png "Logo Title Text 2"

---

## Code and Syntax Highlighting

Code blocks are part of the Markdown spec, but syntax highlighting isn't. However, many renderers -- like Github's and *Markdown Here* -- support syntax highlighting. *Markdown Here* supports highlighting for dozens of languages (and not-really-languages, like diffs and HTTP headers); to see the complete list, and how to write the language names, see the [highlight.js demo page](http://softwaremaniacs.org/media/soft/highlight/test.html).

```no-highlight
Inline `code` has `back-ticks around` it.
```

Inline `code` has `back-ticks around` it.

Blocks of code are either fenced by lines with three back-ticks ```, or are indented with four spaces. I recommend only using the fenced code blocks -- they're easier and only they support syntax highlighting.

```no-highlight
```javascript
var s = "JavaScript syntax highlighting";
alert(s);
```

```python
s = "Python syntax highlighting"
print s
```

```
No language indicated, so no syntax highlighting.
But let's throw in a tag.
```
```

```javascript
var s = "JavaScript syntax highlighting";
alert(s);
```

```python
s = "Python syntax highlighting"
print s
```

```
No language indicated, so no syntax highlighting in Markdown Here (varies on Github).
But let's throw in a tag.
```

(Github Wiki pages don't seem to support syntax highlighting, so the above won't be colourful (the strings are not red, for example). Try it out in a *Markdown Here* email or a Github Markdown README or Github Issue -- you can preview a new Issue without submitting it.)

Again, to see what languages are available for highlighting, and how to write those language names, see the [highlight.js demo page](http://softwaremaniacs.org/media/soft/highlight/test.html).

---

## Tables

Tables aren't part of the core Markdown spec, but they are part of GFM and *Markdown Here* supports them. They are an easy way of adding tables to your email -- a task that would otherwise require copy-pasting from another application.

```no-highlight
Colons can be used to align columns.

| Tables | Are | Cool |
| ------------- |:-------------:| -----:|
| col 3 is | right-aligned | $1600 |
| col 2 is | centered | $12 |
| zebra stripes | are neat | $1 |

The outer pipes (|) are optional, and you don't need to make the raw Markdown line up prettily. You can also use inline Markdown.

Markdown | Less | Pretty
--- | --- | ---
*Still* | `renders` | **nicely**
1 | 2 | 3
```

Colons can be used to align columns.

| Tables | Are | Cool |
| ------------- |:-------------:| -----:|
| col 3 is | right-aligned | $1600 |
| col 2 is | centered | $12 |
| zebra stripes | are neat | $1 |

The outer pipes (|) are optional, and you don't need to make the raw Markdown line up prettily. You can also use inline Markdown.

Markdown | Less | Pretty
--- | --- | ---
*Still* | `renders` | **nicely**
1 | 2 | 3

---

## Footnotes

Footnotes are not supported in standard markdown, but Penflip allows footnotes:

Here is a footnote reference [^1].

[^1]: Here is the footnote.

---

## Escaping Control Characters
```
Sometimes, you need to use plus, minus, underscore, curly and straight braces, backticks and others without them being registered as part of Markdown.

In this case, you use backslashes to escape them, like this: \* \_ \- \+ \{ \] \} \[ \# \` \\
```
Sometimes, you need to use plus, minus, underscore, curly and straight braces, backticks and others without them being registered as part of Markdown.

In this case, you use backslashes to escape them, like this: \* \_ \- \+ \{ \] \} \[ \# \` \( \) \\

---

## Blockquotes

```no-highlight
> Blockquotes are very handy in email to emulate reply text.
> This line is part of the same quote.

Quote break.

> This is a very long line that will still be quoted properly when it wraps. Oh boy let's keep writing to make sure this is long enough to actually wrap for everyone. Oh, you can *put* **Markdown** into a blockquote.
```

> Blockquotes are very handy in email to emulate reply text.
> This line is part of the same quote.

You may notice that the end of the first line above needs to have a *soft-break* achieved by using shift-enter.

Quote break.

> This is a very long line that will still be quoted properly when it wraps. Oh boy let's keep writing to make sure this is long enough to actually wrap for everyone. Oh, you can *put* **Markdown** into a blockquote.

---

## Inline HTML

You can also use raw HTML in your Markdown, and it'll mostly work pretty well.

```no-highlight

Definition list

Is something people use sometimes.


Markdown in HTML

Does *not* work **very** well. Use HTML tags.


```


Definition list

Is something people use sometimes.


Markdown in HTML

Does *not* work **very** well. Use HTML tags.



---

## Horizontal Rule

```
Three or more...

---

Hyphens

***

Asterisks

___

Underscores
```

Three or more...

---

Hyphens

***

Asterisks

___

Underscores

---

## Line Breaks

My basic recommendation for learning how line breaks work is to experiment and discover -- hit once (i.e., insert one newline), then hit it twice (i.e., insert two newlines), see what happens. You'll soon learn to get what you want. "Markdown Toggle" is your friend.

Here are some things to try out:

```
Here's a line for us to start with.

This line is separated from the one above by two newlines, so it will be a *separate paragraph*.

This line is also a separate paragraph, but...
This line is only separated by a single newline, so it's a separate line in the *same paragraph*.
```

Here's a line for us to start with.

This line is separated from the one above by two newlines, so it will be a *separate paragraph*.

This line is also begins a separate paragraph, but...
This line is only separated by a single newline, so it's a separate line in the *same paragraph*.

(Technical note: *Markdown Here* uses GFM line breaks, so there's no need to use MD's two-space line breaks.)

---

## Youtube videos

They can't be added directly but you can add an image with a link to the video like this:

```no-highlight
alt="IMAGE ALT TEXT HERE" width="240" height="180" border="10" />
```

Or, in pure Markdown, but losing the image sizing and border:

```no-highlight
[![IMAGE ALT TEXT HERE](http://img.youtube.com/vi/YOUTUBE_VIDEO_ID_HERE/0.jpg)](http://www.youtube.com/watch?v=YOUTUBE_VIDEO_ID_HERE)
```

---
Still confused? Email support@penflip.com for help!