Understanding the Mac OS X Lion Folder Structure - dummies

Understanding the Mac OS X Lion Folder Structure

By Bob LeVitus

To get acquainted with Mac OS X Lion folder structure, start by looking at the folder structure of a typical Mac OS X installation. Open a Finder window, and click the icon for your hard drive (which is typically called Macintosh HD) in the Sidebar. You should now see at least four folders: Applications, Library, System, and Users.

Within the User folder, each user with an account on this Mac has his own set of folders containing documents, preferences, and other information that belongs to that user and account.

If you’re the sole person who accesses your Mac, you probably have only one user. Regardless, the folder structure that Mac OS X uses is the same whether you have one user or dozens.

Within the Users folder, you find your personal Home folder and a Shared folder, where you can put files you want to share with other users.

All these files are stored in a nested folder structure that’s a bit tricky to understand at first. This structure makes more sense after you spend a little time with it and figure out some basic concepts.

If you display the path bar at the bottom of your windows by choosing View→Show Path Bar, it’ll start to make sense much sooner.


Folders within other folders are often called nested folders.


  • The Desktop is the top-level folder in this example; all the other folders and files you see reside within the Desktop folder.

  • Folder 1 is inside the Desktop folder, which is one level deep.

  • Folder 2 is inside Folder 1, which is one level deeper than Folder 1, or two levels deep.

  • Folder 3 is inside Folder 2 and is three levels deep.

  • The two files inside Folder 3 are four levels deep.

If the preceding list makes sense to you, you’re golden. What’s important here is that you’re able to visualize the path to Folder 3. That is, to get to files inside Folder 3, you open Folder 1 and then open Folder 2 to be able to open Folder 3. Understanding this concept is important to understanding the relationships between files and folders.