150 years ago, the first transatlantic cable transmission was sent from the Queen of England

to the US President, taking 17 hours. 85 years ago, telephones became common household fixtures

and 30 years ago the first cell phone was invented, which weighed as much as an iron,

took 10 hours to charge for a 35 minute conversation, and cost almost $4000.

20 years ago, the first text message was sent - a simple ‘Merry Christmas”

- and today more people have mobile phones than toilets, with around 23 billion text messages being sent per day.

But how the hell do text messages even work?

When you tune a radio to a station, you pick up the information that is being sent out

via electromagnetic waves at a particular frequency - in this case they are radio waves.

These waves mostly just pass through our bodies without interacting at all,

but they are on the same spectrum as the visible light we see, just different in size.

Photons with wavelengths between 400-700 nanometers have the perfect level of energy to excite the rods and cones in your eyes,

which then transmit signals to your brain that you interpret as different colours.

But radio waves, which have wavelengths ranging from 100 microns to 100 kilometers,

are much lower energy and can’t excite your eyes - so they are invisible to us.

Similar to a radio, your cell phone receives signals at specific frequencies, but it can

also transmit its own radio waves back to a network at the same time.

The network is a system of towers, antennas and transmitters which divide a geographical area into ‘cells’

- hence the term ‘cell phone’. These cells determine which areas are served by which towers,

though they generally overlap so that your phone always has a tower to communicate with.

Feel like your phone battery is losing power faster than normal? Phones transmit at higher levels indoors due to building materials,

in rural areas due to greater distance to the network antennas

and when moving at high speeds, like in a car, due to the frequent handover between network antennas.

When someone sends you a text, their phone transmits radio signals, which convey the

identity of both their phone and yours, along with the content of the message.

These signals are then picked up by the tower closest to them, which converts the radio waves into

a digital electrical impulse and passes it along to a hub of the network called a mobile switching center.

If you’re out of range, or your phone is off, the message is stored

by the mobile switching center for a short time until you can be located by the network.

The network then figures out which tower you are closest to and passes the signal there.

Once at the tower nearest you, it’s converted back to a radio signal that can be picked

up by the antenna in your phone. This all happens in SECONDS!

Interestingly, traditional SMS text traffic actually peaked in 2011! Now, most people

send messages via internet services. In fact, last year ‘WhatsApp’ overtook

traditional SMS as the #1 handler of text messaging, managing 30 billion messages sent every day all around the world.

And if you’re sending those messages across the world, it’s actually sent via

a giant cable that runs across the ocean floor.

In fact, 99% of all international data is sentvia undersea cables.

So what does the future of messaging look like? We’re currently in the 4th generation of mobile communication networks, with 5G on the horizon.

And it’s actually been projected

that the technology for phones embedded in our bodies can be available as soon as 2023.

While only a few decades ago it may have taken months to send a love letter,

in just a few years you may be able to simply think of your loved one and send them a message to let them know you care.

We tackle humanity's new forms of communication in The Science of Emojis over on AsapTHOUGHT,

how they’re often misinterpreted, and how to use them properly.

Check it out with the link in the description!

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