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I just followed directions on how to get ubuntu onto a USB thumbdrive using OSX. I can restart my macbook air and hold down the alt/option key and boot into Ubuntu fine.. BUT.. Ubuntu says it want's to run an INSTALLER.. I am afraid if I do that it's going to overwrite my internal harddrive and brick my macbook air... or at least overwrite my OSX filesystem - ... Is it safe to run the installer? will it complete installation in some way on the USB thumbdrive and make it so if I want to run ubuntu I just boot into the thumbdrive and I'm off to the races?
After doing some more reading here it looks like I need to get a second USB THumbdrive and use the installer on the first drive to install Ubuntu 'for real' onto the second drive so that I'm not always in 'live' mode? Is that correct?
I hope my question is clear.