It's impossible these days not to stumble upon a site using Markdown for comment fields, or some open source project that relies on Markdown for formatting their README file. Just go on GitHub. All the documentation over there revolves around .md (Markdown) files.
From a little side project on John Gruber's personal website, Markdown has become the most widely used text-based markup language around. It's currently so big that developers are discussing having an official Spec Team in charge of future updates, just like HTML5, CSS3 and jQuery have.
Markdown is bound to make it to the big time. And this is precisely the reason why you should get acquainted to its syntax and secrets before it gets you by surprise. A good starting point is Strapdown.js, a nifty little tool for embedding Markdown text inside Web pages as regular HTML-formatted text.
The Strapdown.js source code is open sourced and available for everyone via GitHub.
Download Strapdown.js from our Scripts section here.