I remember as a teenager in the 70s having to learn long lists of specials for my after-school job as a supermarket checkout operator. Each week brought a new list of goods and prices, followed by a test.
It was somewhere around the mid-1980s that barcodes started to be widely used. Now we take them for granted, and millions of items are scanned every day at supermarkets, departments stores, airports and elsewhere.
With the correct inexpensive gear we can even use them ourselves at home.
Home use for barcodes
I have a low-cost cataloguing program for books and DVDs, for example. I hold the book’s barcode up to my Mac’s built-in camera, the cataloguing software reads the barcode, looks up the book’s details at an online bookstore, and enters a swag of information into the database.
The key to the barcode is that it can encode a small chunk of data into a few standardised lines that computer software can interpret. That small chunk may be matched by software with a larger chunk. For example, a book’s barcoded ISBN number can be matched with screeds of information from a database.
These days you may see a new kind of barcode around the place. Instead of a handful of vertical lines, the 2 dimensional QR code is displayed as a square filled with black and white pixels. The pixels group together into apparently random lines, shapes and ‘blobs’.
A QR code can encode up to 4,296 characters of text — that’s around 700 words, orslightly more than the average Panui Tip. It can also be ‘smart’, thanks to the QR code reader, and there are many such readers around.
For example, I have a free QR code reader on my iPhone. I snap a photo of a code with my phone, then the QR software decodes it. If it’s an email address or a web address the QR software may then automatically open my email program or my web browser and load the address.
If the code represents a map address, for example, a location on Google Maps, the QR software may automatically open a map and place a marker on the address, while the map software gives me directions.
Text, URLs, other data
QR codes can encode text, URLs, email addresses, Google Maps Locations, Social Network information, contact information, and other data.
They’ve been popping up around the place on websites, as avatars, and maybe even on signs and leaflets.
Imagine the uses for museums and art galleries. Instead of squinting to read a placard in tiny type beside an object, visitors could scan a QR code with their smart phone and read a commentary, visit a website, or view the object’s origins on a map.
To read more about and experiment for free with creating and reading QR codes take a look at the links in the References section below.
Written by Miraz Jordan for, and reproduced from CommunityNet Aotearoa Panui, May 2010. This article has been modified for publication here.