There are three main folders in the macOS Library, which contain essential files and settings for the operating system and its applications.
The User Library folder houses application data, preferences, and caches. It is fully editable, but should be handled carefully to avoid problems.
While it's generally not necessary to manually manage the Library folder, it can be helpful for reclaiming space or cleanly uninstalling apps.
The macOS Library folder contains files and settings used by the operating system and its applications. In most cases, you can ignore it, but it's good to know exactly what it is and what it's for. 📁✨
What is the Library folder and where is it located?
There are at least three Library folders in macOS. All of them store files related to the operating system and the applications you have installed. They can include important system files, scripts, preferences, caches, and more. 📂📄
The first is the System Library folder, located in /System/Library/, which contains files and settings essential to running macOS. This folder is locked; you can see what's inside, but you can't modify it in any way (and you wouldn't want to). 🚫
Next up is the Root Library folder, located in /Library/. It contains files, preferences, caches, and more that are available to all user accounts on your Mac. You shouldn't really need to look in this folder. 🚪
You can edit it, but it's not necessary, and you might break things if you don't know what you're doing. ⚠️
The third is the User Library folder. This is the one you'll be most interested in, as it contains files, preferences, caches, and other items specific to your macOS configuration. It's only available to your user account, and its contents change throughout your daily use. Each user account on your Mac has its own Library folder. 👤📊
The user library is located in /users/[your username]/Library/. It's hidden by default, and for good reason. The folder is fully editable, but don't go around randomly changing or deleting things. You can stop applications or system components from working if you do the wrong thing. ❌💻
The easiest way to open the User Library folder is through the Finder. Click on your desktop or open it from the Dock, select "Go" from the menu bar, hold down the Option key, and then choose "Library." 🔍🖱️
What's in the User Library folder?
Open the Library folder to explore the subfolders inside. 🗂️🔍
For some, it's obvious what they do. The Audio folder, for example, contains your GarageBand loops and plugins; Mail and Messages store your inboxes and message databases; Fonts holds the third-party fonts you've downloaded and installed (system fonts are in the System Library and can't be deleted). Preferences has preference settings for macOS features and your apps. 📧🎵
Some folders have meaningless names, and you can ignore them. If you switch to List view in the Finder window and then click "Size" at the top, you can sort the library contents with the largest folders first. Application Support, Caches, and Containers are usually among the three largest. 📊📋
Application Support contains data and files specific to each application, including things like themes, saved games, add-ons, and other resources that applications need to function properly. 📥
Caches might be the largest folder. Many apps temporarily store data for faster access, and this folder is (usually) where it's stored. It'll be especially large if you use media apps like Spotify, which saves the songs you listen to so you only have to download them once. 🎶💾
Containers are where applications store files and data in an isolated space, where they cannot be accessed by other applications. 🛡️🔒
How to manage your Library folder (and do you really need it)?
The Library folder can grow quite large, though it can also shrink at times, as apps do a decent job of managing things like caches. So, do you really need to manage it manually? 🤔
Not in most cases, unless you're really short on space and need to recover as much as possible. And if you do decide to clean up, you can usually do so through the interface of the app you want to manage. So, you can clear Spotify's cache from within Spotify, for example, or clear your browser's cache in Safari or Chrome. 🧹🕵️♂️
But sometimes it's worth diving into your Library folder to see what you can delete. Some apps, like Discord, don't let you clear the cache, so you have to do it manually. Open Caches, find the app, then identify the cache folder and delete the contents. If you can't find it, check the Application Support folder instead, which is where some apps store their cache. 🚮
macOS also doesn't always uninstall apps cleanly, often leaving behind folders you no longer need. Explore your Containers and Application Support folders to see if they contain anything from apps you no longer have: Adobe and Microsoft Office apps are notorious for not uninstalling properly. 🗑️
You can delete these folders entirely; just be sure not to delete any app folders you still have, or you'll have to reinstall them. ❗️
There are a few more things to keep in mind. If you've added a word to your dictionary that you want to remove, you can do so by finding the Spelling folder and editing the LocalDictionary file in TextEdit. On older Macs, you can often find leftover settings from uninstalled applications in Preferences. You can delete these via the PreferencePanes. 🔤📝
The main user Library folder is hidden for a reason. You don't need to look in it often, and you can cause your apps to stop working if you accidentally delete the wrong thing. But it's helpful to know what the Library folder is and why there are three of them. At the very least, you can free up a few gigabytes by deleting caches when you're really low on space. 💽⚙️
