Adding a function only for the home page

Hi, I've added a function to my functions.php page and it would seem that it's appearing on every page rather than only the home page. Is there a way I can only show it on the home page? I copied the code from another post which was the following: function catcheverest_child_sponsor() { echo 'example'; } // catcheverest_child_sponsor add_action( 'catcheverest_main', 'catcheverest_child_sponsor', 1 ); Thanks Steve