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At a distance

What does telecommunication mean? What does it actually do? What are the basic components of this science that has done so much to change our world and our everyday lives? Here you can find answers to the fundamental questions about communication over distance.

The farside

People imagine telecommunications means communications using only electrical or electronic technology, but that isn't so.

'Tele' is a Greek word meaning 'far off' so the purest definition of telecommunications is 'communications over a distance', in other words, anything that involves sending messages or signals.

Communicating over distance
Over the past 200 years, the distance we've been able to send signals has expanded a million times. The furthest we used to be able to send a signal was as far as the eye could see, or the ear could hear. So the 'maximum transmission distance' was a few miles.

Now we can send signals to the far reaches of the solar system - many millions of miles. The trouble is that it takes many days or even years to get there... As each technology arrives, we discover the limits of its transmission distance - and need to move on to the next.
Communicating at high speed
People talk of telecommunications as 'instant' - but it never is. In fact nothing in life is instant - not even face-to-face conversation. Light and sound move at defined speeds with measurable delays. What matters is the perception of delay - whether it is natural or artificial.

In telecommunications, the technology is rarely the main delaying factor. Human limitations and delays in the system are far more important. So this concept of 'instant' communications is one that has meant different things at different times to different groups of people. Really, it is all a question of what you are measuring it against...
Communicating in different ways
Each of the main technologies of the telecommunications age has used a different type of signal - and a different way of passing messages

Each of those signal types has different characteristics that determine what you can communicate, how fast and how far.

The sound barrier

Suppose you lived in a world with no telephone, e-mail, TV or radio where the only way of sending messages was to send a runner, blow a bugle or shout! It was like that for thousands of years and many people tried to crack the problem. But none of them really succeeded.

In the beginning was the word
The human voice is our most useful and persuasive communications tool - we use it to express our hopes and fears, love and hate, joys and sorrows. For most of our civilised existence, we were only able to do that with people in the same room, street or locality.

These are the most natural forms of communication - the ones that formed the building blocks for everything that followed.
Getting the message
The first writing materials were developed in 4000 BC but how did you get your letter to its destination?

The fastest way of travel was on horseback - so the only way of communicating over distance was by messenger.
Line of sight communications
Most primitive distance communications used visual devices that on a clear day could be seen up to 25 miles away.

If you wanted to send a message further than that, you needed a chain ...
The telecommunications breakthrough
The Industrial Revolution (steam power and mechanical engineering) provided the basic ingredients of the telecommunications breakthrough.

Scientific advances of the 18th and early 19th centuries provided understanding of electro-magnetism and electricity. Now the new machine tools and factories meant better devices could be built quickly and cheaply. The ingredients were in place for the first telecommunications equipment - all that was missing was a need and a market.
The communications time-line
If the whole history of human civilisation was a day, modern telecommunications (the telegraph and all that followed) would only represent our last 30 seconds. That's how recent all of this has been.

But within that time-line, see how much has happened in that last half minute - and how progress is still accelerating, second by second ...

Days of future past

Look at the history of telecommunications and what's happening now, it's tempting to ask: Haven't we been here before? The basic challenges of telecommunications haven't changed much since the days of the telegraph. But the past isn't always a reliable guide to the future.

Deja vu
Throughout the history of telecommunications, you find the same patterns played out again and again - but in different technologies and in slightly different ways.
Where to now
As we stand at the beginning of the 21st century, there are four main trends that are shaping the world of telecommunications, media and entertainment.

Those trends are digitalisation, convergence, fragmenting audiences and the growth of the Internet.
Emerging technologies
Let's take a look at some of the technological developments that are 'out there' and could shape our futures.

Not all of these will work - and there'll be some technologies that aren't on this list - but this is a starting point for looking at the future.
Scanning the horizon
The 'ancient Chinese curse' (there's some doubt as to whether it's even ancient or Chinese) is appropriate to us now. We live in uncertain times with no one quite sure how the world will develop in the 21st century.

There are lots of different factors that could change our world - and technology probably isn't the most important of them. We live in a world of fundamental social and economic imbalances, and one where environmental sustainability is becoming more important every year.

It's impossible to predict what will happen or what telecommunications will look like in 20 years from now. All we can do is look at some of the trends.
fun and games

Can you beat our games? Explode equipment to see what's inside, hear the changing sounds of telecommunications, see how telecommunications designs have changed over time or send an e-postacard.

what's on

The UK's first permanent gallery dedicated to the history of information and communication technologies opens in the new Information Age gallery at London’s Science Museum.

audio history

Take a trip down memory lane with extracts of the interviews which have been recorded as part of the Connected Earth oral history programme.

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