How do I format my posts using Markdown or HTML?

When posting on Cryptography Stack Exchange, you can use the visual editor (for questions and answers, but not comments), Markdown, and some HTML. If you're new to Markdown, you may want to visit the official Markdown syntax reference page.

Here are some tips for common formatting scenarios; more details are available on our advanced editing help page.

Linebreaks

End a line with two spaces to add a <br/> linebreak:

How do I love thee?  
Let me count the ways

New paragraphs only occur when there is a blank line. A single carriage does not create a new paragraph.

Italics and Bold

*This is italicized*, and so is _this_.
**This is bold**, and so is __this__.
Use ***italics and bold together*** if you ___have to___.

Links

There are three ways to write links. Each is easier to read than the last:

Here's an inline link to [Google](http://www.google.com/).
Here's a reference-style link to [Google][1].
Here's a very readable link to [Yahoo!][yahoo].

  [1]: http://www.google.com/
  [yahoo]: http://www.yahoo.com/

The link definitions can appear anywhere in the document -- before or after the place where you use them. The link definition names [1] and [yahoo] can be any unique string, and are case-insensitive; [yahoo] is the same as [YAHOO].

Advanced Links

Links can have a title attribute, which will show up on hover. Title attributes can also be added; they are helpful if the link itself is not descriptive enough to tell users where they're going.

Here's a [poorly-named link](http://www.google.com/ "Google").
Never write "[click here][^2]".
Visit [us][web].

  [^2]: http://www.w3.org/QA/Tips/noClickHere
        (Advice against the phrase "click here")
  [web]: http://programmers.stackexchange.com/ "Programmers Stack Exchange"

You can also use standard HTML hyperlink syntax.

<a href="http://example.com" title="example">example</a>

Simple lists

A bulleted <ul> list:

- Use a minus sign for a bullet
+ Or plus sign
* Or an asterisk

A numbered <ol> list:

1. Numbered lists are easy
2. Markdown keeps track of the numbers for you
7. So this will be item 3.

A double-spaced list:

- This list gets wrapped in `<p>` tags

- So there will be extra space between items

Simple blockquotes

Add a > to the beginning of any line to create a <blockquote>.

> The syntax is based on the way email programs
> usually do quotations. You don't need to hard-wrap
> the paragraphs in your blockquotes, but it looks much nicer if you do.  Depends how lazy you feel.

Tags

To talk about a tag on this site, , use

See the many questions tagged [tag:elephants] to learn more.

The tag will automatically be linked to the corresponding tag info page.

Comment Formatting

Comments support only bold, italic, code and links; in addition, a few shorthand links are available.

_italic_ and **bold** text,
inline `code in backticks`,
and [basic links](http://example.com).

Supported shorthand links:

  • [meta] – link to the current site's Meta; link text is the site name (e.g. "Super User Meta"). Does nothing if the site doesn't have (or already is) a Meta site.

  • [edit] – link to the edit page for the post the comment is on, i.e. /posts/{id}/edit. Link text is "edit" (capitalization is respected).

  • [tag:tagname] and [meta-tag:tagname] – link to the given tag's page. Link text is the name of the tag. meta-tag only works on meta sites.

  • [about] – link to the About page. Link text is "about" (capitalization is respected).

  • [help] - link to the Help Center.

  • [chat] – link to the current site's chat site, the link text being "{site name} Chat".

For more shorthand links, see the expanded formatting guide.

Images

Images can be added primarily by using the the editor toolbar button insert image toolbar button. This brings up a special interface that allows you to upload an image online (through the imgur hosting service) through us - even from your clipboard. Alternatively, it can be input similarly to adding a link:

  • HTML <img src="http://example.com/img.jpg">
  • Markdown ![sample image](http://example.com/img.jpg)