By barcode scanner, it enables the serial number it detects to be transmitted to electronic environment. After this step, the information transmitted (on the computer or terminal) is analyzed and the result is reflected, so that the data entry is realized much faster and more accurately. After the barcode is read with the appropriate reader, the reader converts the black and white lines into electrical signals. The decoder’s decoders turn these signals into numbers or characters we can understand. The electronic signals generated by the beam and barcode bars emitted by these readers are perceived by these readers and transferred to computers as numbers or characters. Dark bars in the barcode absorb light, and gaps reflect light. Thus, electronic signals are formed. Barcode readers can have different interfaces. They can be keyboard, serial port or usb connected. In addition, there are also radio frequency barcode readers. They are wireless and can transfer the scanned barcode to the computer instantly within its own activity area.