Branches of Science
Science describes an area of knowledge, typically about something in the physical world, that can be explained in terms of scientific observation or the scientific method. The scientific method is a discovery process that has evolved over several hundred years and can be summarized as follows:
If the results of the experiments support the hypothesis, it becomes accepted as scientific theory. Later, if new information is found to contradict the hypothesis, it may be revised or abandoned in favor of a new hypothesis, which is then subjected to additional experiments.
The sciences that describe the physical universe are categorized in different ways. The largest distinction in science is whether a science is pure, or theoretical, or whether it is applied, or practical. Pure science explains a phenomenon, while applied science determines how a particular phenomenon may be put to use. In general, pure science is divided into the following categories:
However, these three categories of pure science have areas of overlap, where one type of phenomenon may be associated with another. For example, light (studied in physics) is the energy source behind the (chemical) process of photosynthesis, or food production, in plants (studied in biology). For this reason, distinctions between pure sciences, and even between pure and applied sciences, can blur, and a new compound science can develop. An example of this is biochemistry, in which the chemical processes of living things (such as photosynthesis) are observed and explained.