Hidden, Simple Signals


There have been a lot of discussions recently around the (hidden) tracking dots that printers embed in their output.

It’s got me thinking about the prevalence of simple signals, hidden or obvious, all around us that we often take for granted. Signals, for example, that are more basic than what we normally think of in typical speech and writing—binary.

Ones and zeros

If we pare down a lot of communications (and indeed, anything that a computer does), we find the most fundamental language of computers — the binary ‘on’ and ’off’.

It turns out binary communications reveal a surprisingly useful framework that’s much more prevalent than hidden computer code. It’s in our daily lives, all around us.

You might think that this is too simplistic — as this is the language of computers, but humans aren’t really using binary, right? No — we use binary messages in a lot of ways, in both boring and surprising ways (you know, apart from the obvious ‘yes’ and ‘no’ of casual conversation).

But binary signals have been with us for some time — just think of how lighthouses work as simple “is this thing off….or on” and how critical that’s been to maritime travel. Or we could go even further back in time and look at something like the 5,000 year-old I Ching text and its abstraction of yin and yang. It’s not a new phenomena.

Signals around the world

One place that folks working in the international tech space often encounter binary signaling is when traveling in countries that have widespread pre-paid calling plans. Simply calling someone’s number and hanging up (before you are charged for the call) is a way of signaling to the recipient that they should use their minutes to call back the original caller. And this isn’t a new phenomenon either.

There’s a really great story on Planet Money of an MIT math professor and hedge fund manager Edward Thorpe who in the 1960s was able to prove that the house advantage in blackjack could be beaten by a method of card counting. There’s a side piece to this story where he explains how he was able to use binary signaling with his wife back home without spending a dime on communications.

“And I said, you know, phone calls are pretty expensive. Why don’t we — there’s > a way we can do it without having to spend any money. Here’s what I’ll do.”

“Every night, I’ll call you collect. I’ll ask to speak to Edward Thorp, and > I’ll add a middle initial. That will be like our secret code. So my middle initial is A, that means we’re up zero to a thousand dollars. If it’s a B, we’re up 1,000 to $2,000.”

It’s not limited to phones, either. Remember that ‘Yo’ app craze a couple years ago?

The app (it’s still around) sends a simple message ‘Yo’ from a given sender. It’s not messaging; there’s no nuance around the message. Just a simple ‘Yo’ notification that gets pushed to your device, and it’s up to the recipient to decipher the meaning and value. I remember using the app to have it connected to a rain monitor for Washington, D.C. — so receiving a ‘yo’ from that sender let me know that it was going to rain that day. It sounds frivolous, but the app gained millions of users in just a matter of weeks and was eventually valued between $5 and $10 million dollars.

Of course, there’s also terrifying examples of binary signaling as well. There is an account that in the 60s, the Soviets were investigating means of communications to send/receive signals from otherwise-isolated submarines. There was a thinking that a mother rabbit and her offspring had a ‘psychic bond’ that allowed them to communicate regardless of physical distance or impediments. So the story goes that the Soviets experimented with killing the offspring on land, and recording if there was a change in the mother’s behavior in the submarine.

Start simply and move outwards

First — please don’t consider animal cruelty as a feature of your next app.

I keep coming back to the importance of binary signaling because it helps to clarify the type of data that you actually need as opposed to what you think you need or what would be nice to have. So often in the ICT4D space, the questions we have about our projects are surprisingly straightforward, and we twist ourselves in knots rather than simply asking:

  • “Did your household receive a bednet?” * “Have your children been vaccinated?” * “Do you go to school?” * “Do you have a plan in case of a cyclone or hurricane warning?” * “Do you have enough to eat?”

Often, the simplest questions contain the most important answers.