File used by Zoo Tycoon, a video game that allows players to manage zoos; contains data used for exhibits, animals, and other game objects; used with a .Z2F file to add new game content.
File created by alternative, or non-Windows or Mac, operating systems and GUIs, such as oZone GUI; contains data and objects referenced by the desktop environment, such as menus, text boxes, toolbars, and windows; not meant to be manually opened. NOTE: In the oZone GUI folder, the DL files are located in the "xlib" folder.