In A Short History of Everything, Bill Bryson sets out to explain advances in science in a way that uses everyday language that will appeal to the everyday reader. His goal in particular is to explain to those who are over the age of 30 just exactly how much science has changed in the past decades. The scientific topics he covers include astronomy, the Big Bang theory, chemistry, evolution, geology, paleontology, particle physics, and even quantum mechanics. He separates his book into different scientific subjects and begins each chapter with a frequently asked question, such as, "How did the Universe start?"
Bryson uses the first part of his book to explore the start of the universe and how mankind came to be a part of that universe. He starts out by explaining the discovery of the Big Bang Theory and any holes in the theory. He further explains that the theory cannot "begin to explain how we got here." He then proceeds to describe the new-found theory of how we came to exist.
In Part 2 of his book, Bryson describers how geologists like Henry Cavendish came to calculate the weight of the Earth and further details the shape, size, and orbit of the Earth. He also goes into a discussion of the discovery of dinosaurs and Marie Curie's discovery of uranium.
He uses the third part of his book to delve deeply into physics, such as the theory of relativity and quantum physics. He explains Einstein's theory of space-time continuum and delves deeply into particle physics.
In Part 4, he describes the dangers that threaten Earth on a daily basis, such as the threat of being hit by meteors, the chances of a gigantic volcanic eruption in Yellowstone National Park, a calamitous earthquake, the threat of global warming, and the chances of a new ice age.
He uses his fifth and final section to describe the abundance and diversity of Earth's life forms. He argues that the fact that we all have the same set of control genes demonstrates every life form on Earth came from a shared ancestor. He ends by speaking sorrowfully of extinction and the extent to which extinction is mankind's fault.