Rdoc, the essentials
A short memory jogger.
= Top level title
== 2nd level / sub-title
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A horizontal rule is at least 4 dashes
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Text can be _italic_, *bold* or +monospaced typewriter+.
Verbatim / literal text is indented. But look out
if it's after a list, as they must be idented to a
different extent
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* Indent your lists and use stars
* or hyphens, if you wish
[definition1] you write them like this
[definition2] and the lines can loop over to
the next, so long as they line up
Alternatively:: do labelled lists like this
Do you see:: I'm sure you do
1. This is a ...
2. ... numbered list
a. This is
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Urls / links can be written {like this}[http://go.to/here]
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Now for special characters:
em-dash:: -- or ---
ellipsis:: ...
single quotes:: 'text' or `text'
double quotes:: "text" or ``text''
After all that, I'd actually recommend that you use Yard for documenting Ruby code. It's nicer and more powerful.