Creating installation media for your operating system of choice used to be simple. Just download an ISO and burn it to CD or DVD. Now we’re using USB drives, and the process is a little different for each operating system.
You can’t just copy files from an ISO disc image directly onto your USB drive. The USB drive’s data partition needs to be made bootable, for one thing. This process will usually wipe your USB drive or SD card.
Use a USB 3.0 Drive, If You Can
USB 2.0 has been around forever, and everything supports it, but it’s notoriously slow. You’ll be much better off making the upgrade to USB 3.0 since the prices have dropped dramatically, and the speed increases are enormous… you can get 10x the speed.
And speed really matters when you’re making a boot drive.
Editor’s Note: We use this Silicon Power USB 3.0 drive here at How-To Geek, and at $15 for a 32 GB version, it’s well worth the upgrade. You can even get it in sizes up to 128 GB if you want.
Don’t worry about compatibility, these faster drives are fully compatible with an old USB 2.0 system, you just won’t get the speed boosts. And if your desktop computer doesn’t support USB 3.0 you can always upgrade it to add support.
For Windows 7, 8, or 10
Use Microsoft’s own Windows USB/DVD download tool to create a bootable drive you can install Windows from. You’ll need a Windows installer ISO file to run this tool. If you don’t have one, you can download Windows 10, 8, or 7 installation media for free — you’ll need a legitimate product key to use them, though.
Provide the ISO file and a USB flash drive and the tool will create a bootable drive.
Alternatively, if you’re installing Windows 10, you can download an ISO or burn Windows 10 installation media directly using Microsoft’s Media Creation Tool.
From a Linux ISO
There are many tools that can do this job for you, but we recommend a free program called Rufus—it’s faster and more reliable than many of the other tools you’ll see recommended, including UNetbootin.
Download the Linux distribution you want to use in .ISO form. Run the tool, select your desired distribution, browse to your downloaded ISO file, and choose the USB drive you want to use. The tool will do the rest. You can see a full step-by-step guide here.
You can use similar tools on Linux. For example, Ubuntu includes a Startup Disk Creator tool for creating bootable Ubuntu USB drives.
From an IMG File
Some operating system projects provide an IMG file instead of an ISO file. An IMG file is a raw disk image that needs to be written directly to a USB drive.
Use Win32 Disk Imager to write an IMG file to a USB drive or SD card. Provide a downloaded IMG file and the tool will write it directly to your drive, erasing its current contents. You can also use this tool to create IMG files from USB drives and SD cards.
Linux users can use the dd command to directly write an IMG file’s contents to a removable media device. Insert the removable media and run the following command on Ubuntu:
sudo dd if=/home/user/file.img of=/dev/sdX bs=1M
Replace /home/user/file.img with the path to the IMG file on your file system and /dev/sdX with the path to your USB or SD card device. Be very careful to specify the correct disk path here — if you specify the path to your system drive instead, you’ll write the contents of the image to your operating system drive and corrupt it
Rufus uses FreeDOS, an open-source implementation of DOS that should run whatever DOS program you need to use.
From Mac OS X Installation Files
You can create a bootable drive with Mac OS X on it by downloading the latest version of OS X from the Mac App Store. Use Apple’s included “createinstallmedia” tool in a terminal or by run the third-party DiskMaker X tool.
The Mac OS X drive can be used to install OS X on other Macs or upgrade them to the latest version without any long downloads.
From a Windows ISO for Mac
If you plan on installing Windows on a Mac via Boot Camp, don’t bother creating a bootable USB drive in the usual way. Use your Mac’s Boot Camp tool to start setting things up and it will walk you through creating a bootable Windows installation drive with Apple’s drivers and Boot Camp utilities integrated.
You can use this drive to install Windows on multiple Macs, but don’t use it to install Windows on non-Apple PCs.
Some of these tools overlap — for example, Rufus can also be used to create bootable drives from Linux ISOs, IMG files, and even Windows ISO Files. We suggested the most popular, widely recommended tools for each task here.
Image Credit: USBMemoryDirect on Flickr