Science, the systematic and unbiased study of the world, including everything that can be seen or detected in nature, man, and society, together with the knowledge that grows out of such study. The word science comes from the Latin scientia, meaning "knowledge."

Scientists try to understand, explain, and predict the way in which everything in the world behaves or acts. In pursuing this goal, they study objects, forces, and events as varied as stars, atoms, microorganisms, earthquakes, climate, chemical reactions, magnetic forces, social groups, and human attitudes.

Science has had a profound impact on daily life. The knowledge scientists accumulate about nature, or the physical world, is used to produce tools and machines and to develop technology for agriculture, medicine, manufacturing, communication, transportation, construction, mining, lumbering, and fishing. Scientific findings about human society and behavior influence the methods used in rearing children, teaching students, and treating the mentally ill.

The scientist's method of inquiry, called the scientific method, is what most distinguishes science from other fields of learning, such as philosophy, literature, and the fine arts. In general, the scientific method involves the following steps: state a problem to be solved; collect pertinent data (information) in an objective way; form one or more hypotheses (trial interpretations or explanations); test the most likely hypotheses through objective observation and experimentation; and form a conclusion. The scientific method is discussed in more detail later in this article.

The scientific method is somewhat harder to follow in the study of human society and behavior than in the study of nature. For example, it is generally more difficult to be unbiased in studying social phenomena, such as marriage or suicide, than in studying physical phenomena, such as rocks or plant diseases. Also, it is usually more difficult to perform experiments involving human beings than experiments involving animals, plants, or nonliving matter.

The difficulties involved in following the scientific method in studying human society and behavior have led some scholars to believe that such studies are less scientific than the study of the physical world. However, other scholars believe that these difficulties can be overcome and that both areas of study are equally scientific.