USB Barcode Scanners
Bar Code Scanners with a USB (short for Universal Serial Bus) interface connect directly to a computer (PC or Mac) or to a stand-alone terminal. They obtain their power directly from this connection, and therefore do not require an external AC power supply (which needs to be plugged into a wall outlet).
The barcode data sent by the scanner to the computer port can appear as if it came from a keyboard, also called USB keyboard emulation. The very same cable may also carry serial data from the same scanner (set up as an RS-232 device) to the USB port, hence the term USB COM port emulation.
These types of bar code scanners save operator time and reduce data errors for a wide variety of applications, including point of sale, inventory control, and asset tracking. The barcode scanners listed differ in their total speed-to-read, the total width of the barcodes they can read, and how far they can be from a bar code and still read it successfully.