What is a Disk Images

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What is a Disk Images

I am running OS 10.13.6, High Sierra on a Mac Book Pro 15 inch. I am trying to delete my information on the computer and return it to factory settings to give the computer to another party. In running Disk Utility to perform this task. When I open up Disk Utility, I see

Internal
- Mac - SATA Internal Physical Volume . Mac OS Extended (Journaled) (499.25 GB)
Disk Images
- OS X Base System - Disk Image Volume . Mac OS Extended (1.29. GB)

The disk utility does not allow me to erase the disk image volume. Is that okay before I turn it over to the other party?

MacBook Pro 15″, macOS 10.13

Posted on Dec 31, 2023 9:53 AM

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Answer 1

Top-ranking reply

Grant Bennet-Alder

Level 10

141,571 points

Dec 31, 2023 11:05 AM in response to mkraus54

MacOS Base System is the minimal MacOS that can run Recovery, Disk Utility, and Installer, and little else.

When you see it of size about 2 GB you are seeing the version burned into the Mac's ROM (Read-Only Memory) ready to be pulled out and activated to run Recovery. You can not remove that!

Sometimes you will see MacOS Base System as the name of an incoming MacOS Installer image. But those are far in excess of 8GB these days.

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Answer 2

Dec 31, 2023 9:56 AM in response to mkraus54

You can not erase the drive (disk) you are booted into.

You must do this before giving the computer to someone else:

What to do before you sell, give away, trade in, or recycle your Mac - Apple Support

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Answer 3

Dec 31, 2023 1:47 PM in response to mkraus54

"What is a Disk Image"

a disk Image is like a 'dehydrated' ENTIRE disk, packed into one file that can be easily moved around, copied, and downloaded. When you want to actually use it, MacOS will open it up and pull out an entire disk, with folders inside folders, out of that disk image file, and Mounts its like a 'real' drive.

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