how to create a mobile version for a website?

Firstly, I want to tell you that m.ghi.in is the sub-domain of the main website(www.ghi.in). Many websites display their mobile version on a subdomain of the main website. A common method for creating mobile website is mobile detection method. A server side script is used to detect whether user is using the mobile device or not. When it detects or encounters a mobile device, it redirects the user to the mobile version of the site.
Hope this will Help you