Science is the search for knowledge about the world and the way it works. Unlike the other ways of explaining how the world’s works , science is based on experiments that test theories (ideas).
In the past , people relied on the ancient stories to explain such things as how life began , why the sun appears to cross the sky , what lies beyond the ocean , and so on. These stories often came from religious books or from scholars who dreamed of imaginative ideas without checking them. Because the stories were never tested , there were hundreds of different versions , and every culture had a different version of truth.
How does science work?
Science began when people started to check their ideas about the world. One of the first people to do this was an English Doctor named “William Gilbert” (1544-1603). He carried out many experiments on magnetism and eventually proved that earth is like a giant magnet.
Scientists begin with an idea or “Theory”. Imagine you have a cold but get better after drinking orange juice. You might form a theory that oranges cures colds. To test this , you could give orange to people with colds. If they get better faster than who don’t drink orange juice , the theory is strengthened.
Although scientists can prove that a bad theory is wrong , they can never prove that a good theory is absolutely right. Even if the theory seems correct. Someone could always do a new experiments in the future and prove it wrong. So theories always remain theories.
Since science began more than 2000 years ago , our knowledge of the world’s has increased enormously. Science has lead to many discoveries that have transformed society such as cures for diseases. Its also lead to amazing new inventions such as telephones , televisions , space rockets , and computers. These practical spin-offs of science are called technologies.
Medicine is the science if healing illness. In the past , people believed that diseases were punishment for behavior. Scientists now know most diseases are caused by microscopic organisms , inherited genes or faults with a person’s immune system.
Physicists investigate energy and movement. They study the tiniest particles of matter that make up patterns , and things that aren’t made of matter at all , such as time , light , gravity , and space. The work of physicists led to the discovery of radio waves , which gave us television and mobile phone technology.
All substances are made of chemicals , from your hair and teeth to the air around you and the paper of the books. Chemists investigate how atoms join together in different ways to form molecules , or how molecules break apart and recombine to form new substance.
Biology is the scientific study of living things. Its many branches are devoted to different kinds of life , including botany( the study of plants) and zoology (the study of animals). The most important idea in biology is the theory of evolution by natural selection , which explains how living things came to exist in their current form.
Geology is the study of earth and its interior. Geologists study how rocks form from chemicals called minerals and how they breakdown or change into new types of rocks. Geologists also look at processes that happens deep underground in earth’s interior. These processes causes earthquake , volcanoes , and continually re-shape our planet’s surface over long periods of time.
Planet earth is a tiny speck of matter in a vast universe of planets , stars , galaxies , colossal areas of empty space. Astronomy is the study of this gigantic realm beyond our own planet. Thanks to rocket technology , astronomers can now study space at first hand.