The controller is a physical unit that acts as the brain on the drive. It knows how much space is available and will connect with the machine. Different drives have different controllers.
Our standard is 2.0, but if you need something different (like 3.0, for example) give us a call! One of our product specialists can set up a custom quote for you.
*Please be aware that large HD files with high resolution may have issues transferring through an older 1.0 or 2.0 USB connection.