Mastering Disk Utility in macOS Sierra – Terms in Disk Utility and What They Mean

Disk utility is a utility application designed by Apple for the use of executing disk-related operations across macOS. Disk Utility is the equivalent of Disk Management, a similar program found on Windows.

Even the most casual of Mac users will need to use Disk Utility at some point. Examples include setting up a backup disk or partitioning an external drive, so knowing the basic ins and outs of the program are beneficiary.

This article will define what first aid, partition, erase, restore, mount, and info mean regarding disk utility in macOS. It will also cover some basic uses for each selection and clear up the difference between “restore” and “erase.”

Launching Disk Utility

To access disk utility, press “Command + Space” on your keyboard to open a Spotlight search. From there, type “Disk Utility” and press Enter.


Alternatively, select Launchpad from your Mac’s dock, select the “other” folder, and select “Disk Utility.”



Various Operations and Their Functions

First Aid

First aid will run tests on the selected disk to check for errors. If you suspect your hard drive is not working properly, first aid should be one of the first things to try to attempt to get things running normally.



Partitioning is the division of a single physical drive into two or more sections, sometimes with differing filesystems. This is so that the operating system can handle data in certain regions differently than others. An example of a reason to partition a drive is if one plans on running an operating system other than macOS on a Mac, such as Windows. This is because, again, a different filesystem is used to handle Windows files. Partitioning can happen in a few different locations other than Disk Utility, such as Boot Camp.


When you erase a drive or partition, the space is simply marked as “free.” It is then ready to be overwritten when the system needs the space. Once this is completed, you will be free to partition the space as needed.


A disk restore will make a copy of one volume and restore it onto another. In other words, you are making an exact copy of a whole disk or partition. This option is most commonly used when upgrading or changing hard drives.


Mounting a disk is the act of allowing the computer to read and write data to the disk. In most cases when a disk is connected to the computer, it will automatically be mounted. When a disk is ejected, it can later be mounted again in disk utility. This is done without having to physically unplug and replug in the disk.




Info will detail various stats of a drive, such as the space available in bytes, the overall file count, whether or not the disk is ejectable or encrypted, and more. To view this data, select the target disk in Disk Utility and select “Info.” A new window will open that shows all of the stats of the selected drive.




Knowing your way around Disk Utility is certainly a great way to avoid problems when setting up disks and partitions, and to do so right the first time. Most definitely take a moment to familiarize yourself with the terms, as you will likely need to use the utility eventually.

Corbin Telligman
Corbin Telligman

I'm a junior at UT Dallas, a tech enthusiast, an adreneline junkie, and a coffee fanatic.

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