Somewhere around 1997, I remember my grandfather coming home from a trip to Currys with a replacement for his venerable video recorder. The new one was extra exciting to a small boy because it did something new which its predecessor and my parents’ one did not: it supported Video Plus.
The idea of this was simple: instead of having to key in a day of the week and start/end times to set up a recording, you instead punched in a six or eight digit code number which was printed next to the programme in the TV listings you bought in paper format each week. With your paper newspaper. Because it was the 90s.
As far as I ever thought about it at the time, I assumed the VCR was somehow speaking to a central database which provided the translation of these short codes into the day and start/end times. But, how would that have worked? It was 1997. We didn’t have domestic internet, and even if we had, it would have been dial-up in a different room to the one containing the VCR.
As it turns out, the system was much simpler than that: an algorithm was used to calculate the channel, day of week and start/end times from the code, all done on the VCR locally. Although to muddy the waters a bit, there was an extension to the standard where it was possible to broadcast late alterations caused by over-running sport ot breaking news.
Fast forward quite a lot of years, and you may have heard of What3Words. It’s a system for identifying a precise spot on the surface of the Earth using three dictionary words. Again, as far as I’d ever thought about it, I assumed there was a giant database mapping three word combinations to GPS co-ordinates, and that this is either embedded in their app or accessed online. But no, as it turns out, they have a patented algorithm for turning the three words into the location. Clever.
As has been documented by some, though, it might have been better to design it my way - the algorithm used appears vulnerable to unfortunately similar words mapping to locations rather too close to each other for comfort, if you’re trying to use it to get help in an emergency.