Data
transmitted by the bar code reader to the USB port
appears just like data coming from a keyboard; in
fact, USB keyboard interface can be used to input
data into the same applications that would
typically be used with a keyboard wedge reader. 
A more recent interface available for bar code reading is the Universal Serial Bus interface. Most new PC’s with Windows® 7, Vista, XP, 2000, ME and 98SE and Macintosh® OS support USB HID keyboard attachment. Windows 95, 98 & NT and older computers do not support USB.
Data
transmitted by the bar code reader to the USB port
appears just like data coming from a keyboard; in
fact, USB keyboard interface can be used to input
data into the same applications that would
typically be used with a keyboard wedge reader.