A DMG file is a digital disk image used by macOS to distribute software and operating systems. You typically need a Yosemite DMG if:
The drive will be formatted, so back up any existing data on it. Step-by-Step Terminal Method Plug your USB drive into your Mac. Open (Finder > Applications > Utilities). Select your USB drive and click Erase .
Double-click the downloaded .dmg file to mount it on your desktop. mac os x yosemite 1010 5 download dmg link
You will be prompted to enter your Mac's administrator password. Terminal will not show characters as you type your password; this is normal security behavior. Press again, and wait for the utility to erase the drive and copy the installer files. Once complete, you can restart your Mac while holding the Option (Alt) key to select the USB drive and boot into the Yosemite installation menu. Essential Technical Tips for Legacy OS Installation
Discontinued/Legacy Software Current Support Status: No longer supported by Apple (Security updates ended in 2017). Official Availability: Apple does not provide a direct public web link for Yosemite on its main support pages, redirecting users instead to newer OS versions. A DMG file is a digital disk image
Ultimate Guide: How to Download macOS OS X Yosemite 10.10.5 DMG
Install the OS on multiple Macs without downloading it each time. Open (Finder > Applications > Utilities)
First, it's crucial to distinguish between two types of DMG files associated with Yosemite:
If you need to install Yosemite 10.10.5 on a Mac that has a blank or corrupted hard drive, you can build a bootable recovery USB drive using Terminal. Prerequisites
Released in August 2015, the 10.10.5 update focused on improving the stability, compatibility, and security of your Mac. It addressed specific issues with Mail, Photos, and VoiceOver, making it the most polished iteration of Yosemite. For many users, this version represents the "sweet spot" between the classic Mac aesthetic and the modern flat design language introduced with the 10.10 launch. System Requirements for Yosemite