People and technology

Hey fellas!

Have you stopped to think how technology is present in almost every aspect of our daily life? And how we deal with it in such an automatic way that we don’t even notice that it is there. I find that just amazing. And for me, the less you have to think about it, the more it is accomplishing it’s mission.

So this week I decided to observe how NYC people interact with a really important and widely used piece of technology in the city. The one and only…


If you live in NYC either you must have used one of these or you are an incredibly rich person (who probably doesn’t go out much).

But if you are not from NYC, let me give you a quick explanation about the Metrocard. As the name says, it is the card that you must have to use the subway. You can get one from an agent vendor or at a vending machine. Once you have it you must slide it at at the turnstile to enter the station and catch the train.

So I went to a pretty busy subway stop and just stood there for some minutes. It was quite funny actually and what I noticed were 2 opposite main users: the New Yorkers and the tourists.

The New Yorkers use the Metrocard without even noticing that they are doing so. They are so used to do it that it seems like the card is an extension of they’re bodies, just flowing in a fast way in order to quickly get inside the station and catch the train that has already arrived.

The tourists on the other hand are a lot of fun to watch. First they take several minutes trying to figure out the mysteries of the vending machine. Than, once they finally have the card, hey go towards the turnstile and swipe it veeery slowly, just to make sure that it is gonna work. Meanwhile, they are failing to notice the screen reading “please swipe your card again at this turnstile”. And it is not before they’ve given the unyielding iron bar a few sincere pushes that they decide to swipe the card again, this time in a different speed (sometimes really fast, which doesn’t work either). So after a few goes, a few trains coming and going, and a long line of people behind them without a sympathetic face, they finally make it!

As for the technology on the card itself (the magnetic stripe), I have researched and is actually very simple. Magnetic stripes are made out of thousands of tiny particles of iron oxide, each about 20 millionths of an inch long. Because iron oxide is a magnetic material, all of these little particles are oriented in one of two directions– you can think of them like arrows pointing north or south. When the card is blank, all of these little magnetic particles are oriented in the same direction, and by switching some of the particles around, the stripe becomes “encoded.” Just like binary code (0’s and 1’s) can be interpreted as characters and words and whole computer applications, the magnetic orientation of these particles can be read as information regarding your card’s serial number, balance, expiration, and so on.


The stripe of the card carries three different “tracks,” each with a different type of data. Tracks one and two hold information about the card type, expiration date, times used and remaining card value, while track three is encoded with a unique serial number. One inch of one of these tracks holds 210 bits of data, which translates to about 70 characters. Each time you swipe, your card is both read and rewritten to reflect your new balance.

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