I'm sure a lot of people is thinking that this book is not for them or they are not using this tool, but I recommend you know this tool because it's one of those things that will be useful in the future, if you know it you will recognize where to use it when the problem appears.
Of course, the book is mainly focused on developers and I can say it's direct, clear and really easy to read. You could end it in just 1 hour. After that, you will have all the necessary knowledge to start working with Markdown, from the installation to the implementation in your own products.
Where to buy?
Instant Markdown in Packt Publishing
Instant Markdown in Amazon