Look up numbers, identifiers, and formats

The Story of WTF

I got the idea for WTF a few years ago, when I was selling my old phone online. I took photos of the front and back for the listing, wrote a short description, thought up a minimum price, and set it going.

And then a few hours later, I got a phone call… from myself.

There was just silence from the other end — if I’d heard actual voices, I’d’ve been really spooked — but this was too much of a coincidence for me to ignore. Did someone see the photos of my phone, and, I don’t know, spoofed my number or something? Is that how the system works? What do those numbers even mean, anyway?

It turns out that you can’t spoof calls with any of those numbers. That’s why they’re written on the outside of the phone case, instead of being hidden away. The call I got was just some glitch in the network.

It wasn’t as though, had I known what those numbers meant, I could have looked up what they did. But they didn’t even say what they were; they just said… themselves.

At first I tried reading up on some common formats and making notes that said which numbers were used for what, so I could tell more codes apart by looking at them. But then I realised that if I was going to do that, I might as well turn these notes into runnable, testable code. And if I’m going to write code, I might as well put it on the internet.

In the end, I never memorised of the formats, but I did learn a lot about containers.