Adding multi-language support to web app from the start

I'm about to start a PHP/MySQL based web app and before I start coding I wanted to know how do I incorporate multi-language support? I figured I should develop with the international audience in mind from the start rathe开发者_如何学JAVAr than as an after thought (which most likely will cause slow roll outs to international regions due to having to figure out how to add multi-language support to the web app).

You can look at i18n. Here is some link: http://conferences.oreillynet.com/presentations/mysql06/winstead_practical.pdf