Jekyll is a simple, blog aware, static site generator. It takes a template directory (representing the raw form of a website), runs it through Textile or Markdown and Liquid converters, and spits out a complete, static website suitable for serving with Apache or your favorite web server.
Jekyll is one of the wonderful static site generators available over the internet. Static Site Generators are tools which you use to generate a static version of your site. Instead of using a dynamic scripting language (such as php), your tool takes in your markup & combines it with your blog posts to generate an html only version of your site. This version is then uploaded(eg, via ftp) and is then visible as your blog.
Jekyll at its core is a text transformation engine. The concept behind the system is this: you give it text written in your favorite markup language, be that Markdown, Textile, or just plain HTML, and it churns that through a layout or series of layout files. Throughout that process you can tweak how you want the site URLs to look, what data gets displayed on the layout and more. This is all done through strictly editing files, and the web interface is the final product.
you can learn how to use Jekyll here…
For the code, installation guide and documentation visit Jekyll.