The pursuit of physics is to understand and explain how nature works, from the unimaginably small world of atomic particles to the fantastically vast realm of galaxy clusters. Physicists observe nature and try to categorize and understand the phenomena they observe. Physics is a basic science that is the foundation of many other scientific disciplines and therefore has an important impact on almost all the problems facing modern society. Many people think that physics is something new—but it started before recorded history when people first discovered recurring relationships in the environment. Through careful observation of these relationships and because of nature’s dependability, they found they could make reliable predictions that would seem to give them some control over their surroundings. Physicists solve problems and make discoveries directly through research and indirectly by teaching and inspiring others to look for explanations for the events happening in the physical universe.
Physicists study the natural world, from the tiniest subatomic particles to the largest galaxies. They do experiments to discover the laws of nature. They study what things are made of (matter) and how things behave. They also learn about energy, studying how it changes from one form to another.