Zebra LS2208 handheld laser...
Optical readers with barcode cable.
Cable reader connection is the most cost-effective and most widely used technology in the most common barcode applications.
The USB connection is now the de facto standard, while in the past the "wedge" connection (in keyboard emulation) was mainly used with special "T" cables to connect to personal computers or IBM or Linux terminals, or other hosts.
Most barcode readers still support wedge connections through the use of appropriate cables, to be purchased separately.
Even the RS-232 serial connection, which was widespread in the past, is now scarcely used.