A question a six-year-old asks
Why does anyonewant a barcode?
A barcode was wrapped around your wrist minutes after you were born. It gave you a name a stranger could read without waking you. That is the whole idea, before a single acronym, and it is everywhere in the room you are standing in right now.
start where you are standing
Whatever it is, its barcode has two lives.
to a checkoutAn opaque number only a scanner reads.
to youOr an address anyone with a phone can open. It tells you what the thing is, where it came from, and where it is going.
Every thing below is drawn wearing its real barcode. Each mark was encoded from a real identifier and read back by an independent decoder before this page was allowed to ship. The barcode is the small tag. The thing is the subject.
the drink in your hand
The bottle you are holding has a barcode on the back.
It names the KIND of drink. Every identical bottle on the shelf shares this one number. It says what, not which.
- means
- GTIN
- standard
- GS1
- format
- UPC-A / EAN-13
the bag of lettuce
Same idea, on the back of the bag. One number for this kind of lettuce, the same on every bag in the case.
- means
- GTIN
- standard
- GS1
- format
- UPC-A / EAN-13
the can of soup
And on the can. A retail barcode is just a name for a kind of thing that a checkout already knows how to read.
- means
- GTIN
- standard
- GS1
- format
- UPC-A / EAN-13
the box on the floor
The cardboard box a delivery came in has a barcode too.
Not the drink's number. The box is its own kind of thing, a case, with a number one level up that names what is inside and how many.
- means
- GTIN-14
- standard
- GS1
- format
- ITF-14 / GS1-128
the same thing, twice
A barcode can name a kind, or it can name this one.
The barcode on the back of a 12oz bag of lettuce is a GTIN. It names the kind: every identical bag in the case carries the very same number. Useful at a register, which only needs to know what to ring up.
Give THIS bag its own serial and the number changes meaning. Now it is an SGTIN, and it names this one bag and no other, with a history that is only its own. Same GTIN, different SGTIN.
a 12oz bag of lettuce
- means
- GTIN
- standard
- GS1
- format
- EAN-13
THIS bag, and no other
- means
- SGTIN
- standard
- GS1
- format
- QR
the same split, at the pharmacy
Over the counter it is a kind. On prescription it becomes this one.
An over-the-counter medicine is a class, one GTIN for the kind. The moment a pharmacy fills a prescription, the same drug is serialized: a GS1 SGTIN with a batch lot and an expiry, in the square pharmacies actually print, a GS1 DataMatrix. The hospital keeps one exception: devices and supplies are serialized too, but a reusable surgical tray is not. It goes through the autoclave and comes back the same asset, a GRAI.
an over-the-counter box
Off the shelf, a pain reliever is a class. One number for the kind, the same on every identical box.
- means
- GTIN
- standard
- GS1
- format
- UPC-A / EAN-13
a prescription bottle
Filled at the pharmacy, the same medicine becomes this one: a serial and a batch lot and an expiry, in the square a pharmacy actually prints, a GS1 DataMatrix.
- means
- SGTIN
- standard
- GS1
- format
- GS1 DataMatrix
a surgical tray
A reusable surgical tray is the exception. It goes through the autoclave and comes back the same asset, a GRAI, not re-serialized each cycle.
- means
- GRAI
- standard
- GS1
- format
- GS1-128
now zoom out: the box did not come alone
The box did not travel alone. It rode on a pallet, stacked with its case-mates.
a pallet
The pallet is one thing too, a logistic unit, and it gets its own number, made fresh the moment it is built and never reused.
- means
- SSCC
- standard
- GS1
- format
- GS1-128
The pallet rode inside a shipping container. And here the same steel box starts answering to more than one name.
a container
As cargo, it carries its own container number, an ISO 6346 code (owner, serial, a check digit) stencilled on the door. Book it and the same box is a fixed asset with a GIAI. Bolt it to a chassis and the rig on the road is a vehicle with a VIN, though that number names the truck, not the box. One steel box, three identities, depending on who is asking.
the container number, an ISO 6346 marking on the door. Named, not drawn: this door reads GS1 and VIN marks, and does not mint a container-number symbol.
A car on the same road makes the transformation plain.
a car
On the lot it was a product with a price. The day a company buys it and books it, the same car becomes a capitalized asset. The thing did not change. Its role did.
- means
- VIN
- standard
- ISO 3779
- format
- Code 39
The laptop a company hands you is the everyday version of the same move.
a computer
Bought as a product, tracked from then on as a fixed asset with its own permanent number, the one on the little sticker underneath.
- means
- GIAI
- standard
- GS1
- format
- GS1-128
Not everything is used up and thrown away. Some things come back.
a returnable tote
A tote, a keg, a pooled pallet: numbered as a returnable asset, sent out, brought home, and sent out again, the same number for its whole working life.
- means
- GRAI
- standard
- GS1
- format
- GS1-128
the thread through all of it
One person wears a different barcode for every relationship.
You are not a product, and you do not have one number. Across a life you wear many: a transit pass, a gym card, the patient band from the day you were born, the license in your wallet. Each one is a different relationship with a different meaning. The barcode names the relationship, never the person.
a patient band
The hospital wristband from the day you were born. A service number that ties every reading and every medicine on the ward to the right patient, so nobody has to ask twice.
- means
- GSRN
- standard
- GS1
- format
- GS1-128
a transit pass
A transit pass. Tap in, tap out. The number is your standing relationship with the service, and it names that, not you.
- means
- GSRN
- standard
- GS1
- format
- GS1-128
a gym card
A gym card, a clinic record, a loyalty account. Each is a relationship between you and a service, and it gets a number of its own.
- means
- GSRN
- standard
- GS1
- format
- GS1-128
the license in your wallet
A driver's license carries a barcode too, and we can tell that it is one. We decline to read it.
- means
- driver's license
- standard
- AAMVA
- format
- PDF417
and the things that are not things
A shipment, a service, a document. No shape to hold, and a barcode all the same.
A bill of lading, an invoice, a receipt: these are not objects, they are the record of something that happened between two parties. A QR Digital Link can carry the document's own fields inside it, so the barcode is not a pointer to the paperwork. It is the paperwork.
- means
- Digital Link
- standard
- GS1
- format
- QR
Your turn
Read your own. The read never leaves your tab.
what it said
(01)09506000134352(17)261231(10)ABC123(21)1234
check mod10 pass — computed from the digits
the register takes this
the price lookup, exactly as it happens today
and drops these
the floor
Get an API key.
The local verbs run from npx barcoding.dev today with no key. A key opens the network half of the verb set.