You can look at the URLs when SEF is turned off on your website. The ctrl parameter is the "view". The "task" parameter is sometimes the "file".
Then, some view files call other view files based on your settings or to have stuff neatly arranged. For example, the show file of the view product display the product page. But most of it actually displayed in the show_default view file which is the default product page layout that it in your configuration. Then, that view file calls all the different pieces of the interface like show_block_img, show_block_characteristic etc