About Laser Barcode Scanners on Windows and Android.
Barcode scanners will usually operate in what is known as "keyboard wedge". The term wedge comes from the fact that the hardware device typically sits, or wedges, between the keyboard and the PC or device. A scanner set to "keyboard wedge" just means that it acts like a keyboard and enters the numbers represented by the barcode, just as in a keyboard where you type the number and press the return key at the end.
The barcode scanners with keyboard wedge output usually plug directly into a USB port on your PC or are attached by Bluetooth to your device.
If your scanner is not behaving as expected you can check to see what your scanner is sending by scanning the barcode into a text editor or another application such as AirPOS. The barcode number should appear with the cursor positioned below it ready to scan another barcode (or in the case of AirPOS it will report the number and say 'Not found'). If you press the backspace key once does the cursor move to the end of the number or is there a space between the last digit and the cursor? (Some barcode generators will put a space there so it's advisable to take a look at just what is being scanned before entering all your barcodes).
If when you scan, the barcode is appearing elsewhere such as the URL of a browser it could be adding a tab instead of a return. In that event you'll need to consult the hardware manual for your particular scanner in order to set it to 'Keyboard wedge". This is usually done by scanning a reset barcode followed by another to set it to "keyboard wedge". Some manuals may refer to this as setting the scanner in HID Mode (Human Interface Device).