You didn’t even realize there are different versions of the installer? It turns out that when you download the Mountain Lion installer from the Mac App Store, that copy of the installer installs whatever version of OS X was available at the time of download. If you don't, you'll have to re-download the installer from the Mac App Store before you can create a bootable install drive.)Get the latest version of the Mountain Lion installerBefore you make a bootable install drive, you should make sure you have the latest version of the Mountain Lion installer. 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. That said, if, for whatever reason, you absolutely need to create a bootable install DVD, follow steps 1 through 5 under “,” below, but from Step 6 on, follow the instructions under “To create a bootable DVD” in.(Note: As explained in, 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. 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.

I show you how, below.You may have noticed that I didn’t mention making a bootable install DVD. Also, if you need to reinstall Mountain Lion, recovery mode requires you to download the entire 4GB+ installer again.) Finally, if you need to -assuming you have the license to do so-a bootable install drive makes it easier to do so.Thankfully, it’s easy to create a bootable install drive from the Mountain Lion installer that you download from the Mac App Store.

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