You may have noticed it, but don’t know what it does. You may have used it, but it doesn’t appear as a shortcut in Finder. Library folders are central OS X structures. Most are best left alone, but it’s useful to know your way in and around the User Library.
Mac OS X Library Folders
Most of the files you use on a daily basis are located in one of several popular home subdirectories: Downloads, Documents or Desktop. These are the files you actively use and move around; pictures, documents and downloaded files. Applications and system processes keep their data — cached mail, default desktop backgrounds and system preferences — in the Mac OS X Library folders.
For lack of a better way to put it, these Library folders are the default storage location for your system and the applications that run on it. These files are used by applications and you won’t usually access them directly. Users will sometimes venture in these Library folders to retrieve system and application logs or application data. For instance, to synchronise your applications over Dropbox.
The Different Library Folders
There are two main Library folders you might concern yourself with: the main Library folder and the user Library folder.
The main Library folder is located on the root of your hard driven, located at
/Library. It’s a folder that’s shared among all users, so this is where you’ll find your screen savers, default backgrounds and applications that share the same data or preferences with all users on the system.
Each user also has a Library folder in his or her home directory, located at
~/Library. In later versions of Mac OS X the Library folder is hidden by default, but it’s located on the same level as your Downloads and Documents folders. This Library contains only per-user data and preferences. Most Mac OS X applications will use this folder to store their data, so this is the Library most people are concerned with.
Those are the most relevant Library folders, but there are two we didn’t mention. Network administrators may set up a
/Network/Library folder to share data across users of a single network. Finally, the System Library is located at
/System/Library and contains data that your operating system uses.
Be Careful Poking Around
Whenever you delve into a Library folder, keep in mind that there are applications and system processes that rely heavily on this data. Manually clearing a cache may fix a malfunctioning application if you know what you’re doing, but it’s just as easy to break an application if you stumble around blindly. Be cautious when working with Library folders and, as a general rule of thumb, if you don’t know what it does you should leave it be.
This is doubly true for the
/System/Library folder. Contained in this library are files that are crucial for your system’s operation. Rummaging around in the System Library doesn’t just have the potential to break an application, it can corrupt your entire system. Even most advanced users don’t have any reason to manipulate System Library files. As a general rule of thumb, stay out of this folder. Seriously.
How To Access Your User Library
If you checked in your home directory, you probably won’t be able to find the Library. On Mac OS X 10.7 Lion and later, the user Library folder is hidden by default (not necessarily the biggest Lion annoyance, though). Most people won’t need to access it, so it’s safer to hide it altogether. Even if it’s hidden, you still have a few different options for accessing your user Library.
Finder’s Go Menu
The Go menu in Finder contains links to most popular user folders. Library isn’t usually listed, but it appears if you hold the alt (option) key. This is a quick and easy way to access your user Library folder, and the best option if you don’t often need to access it.
Always Show The Library (OS X Mavericks)
If you need more frequent access to your user Library, consider unhiding it permanently. Starting from Mac OS X 10.9 Mavericks, this has become very easy. Use Finder to browse to your user home directory and select View > Show View Options. At the bottom of the options panel, tick off the checkbox next to Show Library Folder.
Always Show The Library (Terminal)
If you’re running an older version of Mac OS X, you can use the Terminal to unhide the Library folders. Open the Terminal from Applications > Utilities > Terminal and enter the following command:
chflags nohidden ~/Library
Press enter and enter your administrator password to confirm. If you want to hide your Library folder again in the future, you can use the following Terminal command:
chflags hidden ~/Library
Wonder what else you can do with the Terminal? Check out these 6 Terminal commands to give your MacBook an extra boost.