Formatting Text Using Custom Markdown With Javascript Or Jquery

I run a site where users submit basic news articles. I want to add some formatting features for their submissions, quite similar to the markdown feature used here. For example, use

Solution 1:

The Markdown solution that Reddit uses is freely available, lightweight, well documented and does everything you asked for and more:

http://daringfireball.net/projects/markdown/

Solution 2:

Please have a look at this pluggin markitUp!

markItUp! is a JavaScript plugin built on the jQuery library. It allows you to turn any textarea into a markup editor. Html, Textile, Wiki Syntax, Markdown, BBcode or even your own Markup system can be easily implemented.

Hope this will help you.