This volume is completely separated from all other data to prevent accidental overwriting of critical operating system files. Which one to erase, Macintosh HD or Macintosh HD - Data? Erase Macintosh HD volume when reinstalling macOSĪs aforementioned, Macintosh hard drive volume serves as the system volume on Mac. In the Finder, they show up as one integral Macintosh HD volume. Though the two volumes do different jobs, they have something in common. Besides, unlike read-only Macintosh hard drive volume, Macintosh HD - Data is fitted with full read-write access. Macintosh HD volume loads the Mac system files and scripts while Macintosh HD - Data volume stores personal data on Mac. The biggest difference between Macintosh HD and Macintosh HD - Data is that the stored file contents differ. The file system of this volume is also APFS or APFS (Encrypted) by default and can’t be reformatted to other file systems. Mac users have read-write access to this volume, which means Mac users can edit and manage files on Macintosh HD - Data directly. The Macintosh HD - Data volume is used to store Mac user files such as documents, videos, photos, and audio. Macintosh HD - Data is the other separate entity of the Mac hard drive. It can't be reformatted to other file systems. The file system of Mac hard drive volume defaults as APFS or APFS (Encrypted). That's because Macintosh HD contains the macOS files and the Mac won't turn on once these files are modified or deleted.

Mac users can't erase, delete, or edit this volume. Macintosh HD is designed to store the operating system files and applications only, which is also called the system volume. Which one to erase, Macintosh HD or Macintosh HD - Data?įrom macOS 10.15 Catalina, the internal hard drive of a Mac is segregated into two separate entities. Some Macs may show macOS and macOS - Data these two volumes as well.īut why there are Macintosh HD and Macintosh HD - Data? In this article, we provide a straightforward and informative overview to help you understand what they are and the difference between Macintosh HD and Macintosh HD - Data. And you will know which one you should erase when reinstalling or downgrading macOS. If you have updated to macOS 10.15 Catalina and later on your Mac, you must have noticed that there are two volumes in Disk Utility, one named Macintosh HD, and another called Macintosh HD - Data.

What is macintosh hd