Normally, whenever you start up your computer, it boots from the operating system stored on your internal hard drive. This could, for example, be a Windows installation CD. A “ bootable USB” is a regular USB storage device (like a USB stick or external hard drive) that has an “ISO image” of an operating system saved on it.Īn ISO image is an archive file that contains all the information found on an optical disc, such as a CD or DVD.
