Index Of Content Babes How Does Google Index Pages On Which The Content Stays The Same But The File Extension Changes?

How does Google index pages on which the content stays the same but the file extension changes? - index of content babes

I am pleased with the changes along to my site to another friend of mine production, but my current page in ASP models and the new model is in PHP. What must I do to keep Google index all the pages with the new model of the site or make the same, but it is only in PHP? Should I again on each page of my site on Google using the file extension?