CakePHP 1.2 introduced .ctp as its file extension for views.
CakePHP view files are written in plain PHP and have a default extension of .ctp (CakePHP Template). These files contain all the presentational logic needed to get the data it received from the controller in a format that is ready for the audience you’re serving to.
http://book.cakephp.org/2.0/en/views.html#view-templates