# Understand a scanner prefix and separator

Use the observed separator to distinguish a lot from the following date.

Source: https://help.smartfact.ai/barcodebench/guides/scanner-separator

Audience: Operator

This lesson uses made-up values. BarcodeBench checks the text received, not the physical print quality, ownership or correctness of a shipment.

## Understand a scanner prefix and separator

1. **Start a barcode check**

   Start a barcode check.

   Start a temporary session. Values stay on this device and are not sent for a remote lookup.

2. **Open the made-up examples**

   Open the made-up examples.

   Use a prepared example with a real hidden separator. Typing the characters \[GS\] would not create that separator.

3. **Choose the scanner separator example**

   Choose the scanner separator example.

   Choose the example as a scanner could send it, including its prefix and the hidden separator.

4. **Choose how to read the value**

   Choose how to read the value.

   Move to the format choice before asking BarcodeBench to explain the value.

5. **Read the lot and expiry separately**

   Read the lot and expiry separately.

   The actual separator keeps the lot and date apart. The result also tells you that the scanner prefix was left out of the checks while the original stayed unchanged.

[Watch or practise this chapter](https://help.smartfact.ai/barcodebench/demo?guide=scanner-separator&chapter=scanner-separator)