So if you plan to use that installer on other Macs, or-in this case-to create a bootable drive, be sure to copy the installer to another drive, or at least move it out of the Applications folder, before you install. Our main Mountain Lion-installation article, if you leave the Mountain Lion installer in its default location in the Applications folder when you install OS X 10.8, the installer will be deleted automatically after the installation finishes. Our article on making a bootable Lion-install drive. Using Disk Utility,” below, but from Step 6 on, follow the instructions under “To create a bootable DVD” in That said, if, for whatever reason, you absolutely need to create a bootable install DVD, follow steps 1 through 5 under “ In addition, you can easily update a USB stick or external hard drive each time an update to Mac OS X is released, as explained below with a DVD, you have to toss the disc in the trash and start over, which is both a hassle and bad for the environment.

More and more Macs ship without a built-in optical drive booting and installing from a DVD is very slow and 8GB flash drives can be found for $10 or less-there’s little reason to opt for a DVD anymore. Though it’s possible to make one, I don’t recommend it these days. You may have noticed that I didn’t mention making a bootable install DVD.

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