Pages are one of WordPress's built-in features. You'll probably want most of your website Pages to look about the same. Sometimes, though, you may need a specific Page, or a group of Pages, to display or behave differently. This is easily accomplished with Page Templates.

ok sir i am not under stand ur answer .
i create a own page slide.php my question is how to set this to home page of theme some middle data of a same page
i am learner of wordpress programer give me some advantages and how to create own pages to themes