Listening recently to Billy Joel's "We didn't start the fire" I thought about expressing history in single words. One of my favourite conversation starters is to ask people who the most remembered person of the 20th century will be in the 25th. (For the 15th century, the clear winners are Columbus, Leonardo, and Gutenberg, with Columbus the stand-out in the Americas.) When I ask, people will pick names like Hitler or Einstein. Based on Columbus' example, I think Neil Armstrong is a good contender, even though he can walk down the street today without being recognized.

So I came up with a challenge. Write the history of the 20th century in a single word as it will be perceived in centuries to come. In other words, "what's from the century will be deemed most significant by the people of the future?" This is easier to do for centuries further past, because what people consider most important about the 20th century will depend on their own more recent history.

You'll note that with a few exceptions, my words refer to science and technology, not politics, people, arts or philosophy. Because I feel these things affect the lives of the people far more. Wars may redraw borders and decide who is ascendant. History is written by the winners, but there is always a winner to write it. So you won't see items most historians would list, like WW2, in my top 5.

20th Century

Computer

My first choice, both because computers are now the prime tool of all the other fields, as well as the controllers of almost all industry, and they will be much more. In fact, I believe the people of the future will be computers, or part computer, and thus consider this the most significant invention of the 20th century.

DNA

(Or "genomics" if you don't think of DNA as a word.) We we rewrite who we are (if we don't become computers) with this knowledge.

Nanotechnology

This is a tricky one. It was conceived in the 20th century (in the 50s in fact!) but not implemented within it. So perhaps it belongs in another century, but it may as well become the foundation of all manufacturing, and of ourselves.

Nuclear

In the 20th century we came to understand much lower levels of physics, but we're not done. But if nuclear weapons destroy the world, this will make the cut.

19th Century -- Electricity

From our 21st century viewpoint we can see how much that altered the world, along with the things that came from it, like telegraphs, phones, radios and even computers.

Other contenders: Industry, Germs and Evolution

18th Century -- America

My one political event. The free constitutional democracy would change the world. We know that today. In 1805 people would have thought this a crazy one to put on the list. Other contenders, the start of the Industrial Revolution, and Vaccines.

17th Century -- Science

The scientific method traces back to ancient days, and owes much to some earlier figures like Roger Bacon, but it was in this century that it truly flowered. The other contender: Steam

16th Century -- Conquest

Perhaps this is biased by being in the Americas, but this was the century of world exploration and conquest, mostly by European powers. Other contenders: Astronomy

15th Century -- Firearms

In particular the Arquebus and Rifle. The musket would come later. The firearm set the stage for all wars to come. Another big contender, Gutenberg's press.

What are your contenders for these centuries and others?