Its very easy to know about usb ports, grey color indicates the USB 2.0 and blue color indicates the USB 3.0, the big different between USB 2.0 and USB 3.0 is speed, USB 3.0 is ten time faster than USB 2.0 and its power efficient also, let see how to identify usb type.
1. To identify usb type check the laptop port like grey and blue colors OR
2. Right click on “this pc/my computer” select “Mange” click on “Device Manager” and extend the “Universal Serial Bus controller” here you will find all the detail about ports.