A Screenshot
All WordPress themes have a screenshoot image included – typically this is called “screenshot.png”, is 600 x 450 in dimension and is a visual display of the theme, which can be seen on the Appearance > Themes page inside your WordPress dashboard. Since child themes have their own folders and are activated like any other theme, they require a screenshot like a standard theme.
Theme Files
The Genesis Framework, which in essence is the parent theme, is where all of the theme files are kept. This would include the typical theme files such as 404.php, comments.php, footer.php, header.php, index.php, page.php, single.php and so on. Child themes can also include these files – and the hierarchy works in a way that if any of those files exist in the child theme folder, they will override the parent theme. In other words, if you customize a footer.php file and place it into your child theme folder, that will be used in lieu of the one in the Genesis parent theme. Currently the only theme files that may be found in some of the Genesis child themes are a custom home.php file, which will control the way a site’s homepage will appear. If one is not a part of a child theme, then the theme will use the index.php file, in the Genesis-parent theme, for the homepage.