[eluser]Sumon[/eluser]
i think, .php for model and controller, .html,.php for view. From my point of view, it's not limitation as Microsoft word file save with extension .doc
one further point is that, model and view extension never shows to visitors. instead they only view the URL. CI have an excellent feature in application/config/config.php file
Code:
$config['url_suffix'] = ".jsp";
this line of code automatically add .jsp at the end of URL.