30 Second

If you only have 30 seconds, there is time—using this book—to bone up on how to eat well. We're served a daily diet of food facts, fads and often far-fetched claims for what we put on our plates, which makes it difficult to distinguish healthy from harmful. With obesity, heart disease, diabetes and other life-threatening conditions rapidly rising, it pays to understand that we are very much what we eat and that good food—in the right proportions and portion sizes—is essential for our health and well-being.

Universal change is often the result of an individual's lightbulb moment – an invention that triggers a ripple effect across countries, continents, or even out into space. Great Inventions in 30 Seconds looks at fifty of these groundbreaking innovations – great ideas that really did change the world. It covers a wide range, from early days (the wheel) through materials (the invention of steel, for example, or plastic) to communications (the alphabet, the printing press, the Worldwide Web) and the conveniences of (relatively) modern daily life (refrigeration, indoor plumbing, central heating).

Almost two centuries since his death, Napoleon Bonaparte remains the subject of vigorous debate. On one side are those with a romantic attachment to ideals of liberty and democracy, on the other are those who would rather see him as an ambitious warlord, bent on establishing a colonial empire in the heart of Europe.

Do you know your fission from your fusion? You will have heard of Einstein's theory of relativity and his synonymous equation E=mc2, but do you really understand what they mean? With renewable energy a hot topic of conversation, arm yourself with the 50 most significant theories and developments that will allow you to contribute to any debate about this integral force in the universe.

Weather and climate are not the same. Weather is what occurs outdoors on a daily basis and is unpredictable from one week to the next, whereas climate follows a stable pattern that is developed over centuries. The planet is divided into climate zones—tropical, temperate and polar—based on temperature differences with distance from the equator where the sun is most intense and temperature affects humidity, precipitation, cloudiness and wind.

Genetics is the study of heredity, and reveals how the characteristics of living organisms are determined by the genes passed down the generations.

If you only have 30 seconds, there is time—using this book—to bone up on how to eat well. We're served a daily diet of food facts, fads and often far-fetched claims for what we put on our plates, which makes it difficult to distinguish healthy from harmful. With obesity, heart disease, diabetes and other life-threatening conditions rapidly rising, it pays to understand that we are very much what we eat and that good food—in the right proportions and portion sizes—is essential for our health and well-being.

Who invented photography first, Fox Talbot or Louis Daguerre? Who got the patent? Who made the most money? Who are the greatest photographers and what have their contributions been?