The shower bar code or otherwise known as hand readerdiffers from the scanner by the greater mobility of the device. Quite compact in general, this bar code reader is taken in hand and by a simple pressure on the trigger or the button allows you to read the bar code.
Some models of shower bar code can, by being put on a support, fire alone when you present a code in front.
Several techologies exist: CCD) hand shower (contact), laser, imager... On the other hand, the choice of your reader also depends on the type of bar code you want to read: linear 1 d or 2D QR Code.
Finally, if you need to move with your bar code reader, some models are wireless and operate on battery power. You can get to the bottom of your warehouse for example to scan your bar codes.