Windows system on the use of UltraISO to make CentOS start USB disk method:

1. Download the latest version of UltraISO (I use the latest version), do not repeat here.

2. Start UltraISO, click on the "File" menu under the "Open" button, open the prepared ISO image files, such as Centos-7-x86_64-minimal-1511.iso, at this point the red circle below will display the "bootable CD" word.

3. Click on "Start"-> "Write Hard image", the hard drive is already inserted into the U disk, write the way is usb-hdd+, click the "Write" button. After the completion of the installation of U disk is done.