] Create a bootable Linux USB from Windows If you are running Windows, your best bet is to use rufus, a free and open source USB writing tool.

Perhaps they referenced this guide to create a bootable Live USB on Windows, allowing them to test drive something like Ubuntu without making any changes to their PC.

How to make a bootable USB drive If you're trying to install a new operating system or flash your BIOS, you're going to need a bootable USB drive - here's how to make one.

There you have it — a bootable copy OS X Mavericks on USB Flash Drive that can be used to install, upgrade, and/or troubleshoot compatible Apple computers.