How to control what text is displayed on featured slider?

I was wondering if it is possible to control what text is displayed with the featured image on the homepage slider.

This text is called Excerpt and it can be controlled for each Post individually. When editing Posts you will see a field called Excerpt under Post Edit area and this is where you can add your custom text.
If you can’t see Excerpt field you can enable it via Screen Options on the upper right corner in Post Edit view.

Thanks for the reply. I am creating a website with pages only and not posts, is there an option to do this with pages??

It is possible, however, you will have to use plugin or enable it via functions.php. I guess the simpler method will be to get this done by using plugin.

Here is one of those plugins which will enable excerpt field for pages: http://wordpress.org/plugins/page-excerpt/