Mac OS X Panther in a Nutshell, 2nd Edition

Folders

Folders, also referred to as directories (especially in a Unix context), give disks a hierarchical structure. A disk can hold any number of files and folders, and these folders can contain more files and other folders, ad infinitum.

Folders are colored blue by default, although some applications like to include their icon on the folder as well. This is similar to the default folders in a user’s Home directory, which have icons to suggest their intended use. For example, the Documents folder has a generic document icon, the Library folder has four book icons, etc.

If the Finder is in Icon or List View, double-clicking a folder causes its contents to appear in a Finder window. Double-clicking a folder in Column View just displays the contents of the folder in the next pane to the right, as if you had single-clicked on the folder. If you double-click a folder on the Desktop, that folder opens in a new Finder window of its own in the default View (which is Icon View, unless you’ve selected Column View in the Finder’s preferences; see earlier). You can go back to a folder’s parent folder or disk by selecting Go→Enclosing folder in the menu bar or with the keyboard shortcut, -Up Arrow.

If you hold down the Command key () and double-click on a folder, the folder opens in a new Finder ...