Sub-folders are shown within their parent by default. If you activate this option, sub-folders are displayed on their own. It looks less nice but it may help if you have a very big folder you want to spread in two columns.
Les subcarpetes es mostren dins el seu pare per omissió. Si activeu aquesta opció, les subcarpetes es mostren soles. Sembla menys agradable, però pot ajudar si teniu una carpeta molt gran que voleu expandir- la en dues columnes.