Themes provide the styling and layout of your site. They determine how the various templates are displayed and can be customised using site skins.
The Chill theme displays content in left, central and right hand columns. It has customisable top and side menus, and a Home template that can display content in blocks or tabs, with an optional carousel.
The Impact theme works well with an image-rich site, displaying large blocks of content as panels on a page. It includes a carousel that appears behind the header, parallax scrolling, and a variety of tab, square, block and list panels.