you can render it un readable by standard devices
Probably not, but black on white is easier for the bar code scanner to "read"
6748303023
2516
black
Like this ▅▆▇█████▇▆▅
A bar-code reader.
Keep black people in Jails around New York area
It is a set of parallel black and white lines, with a row of about 20 numbers underneath.
A bar-code reader.
Bar codes have a meaning because the meaning of a bar code is assigned to that bar code. A bar code identifies an item, and product information regarding that item is held in a data base.
The level of measurement of a bar code is nominal.
"bar code" contains 7 letters.