Science is a systematic discipline that builds and organises knowledge in the form of testable explanations about nature and society. It is driven by the scientific method: an empirical cycle that typically involves making observations, producing hypotheses, testing them with evidence, and drawing conclusions. Science encompasses this process and the body of knowledge it produces, which the scientific community continuously challenges, validates, and organises.

Modern science is typically divided into two – or three – major branches: the natural sciences, which study the physical world, and the social sciences, which study individuals and societies. While referred to as the formal sciences, the study of logic, mathematics, and theoretical computer science are typically regarded as separate because they rely on deductive reasoning instead of the scientific method as their main methodology. Meanwhile, applied sciences are disciplines that use scientific knowledge for practical purposes, such as engineering and medicine.

The history of science spans the majority of the historical record, with the earliest identifiable predecessors to modern science dating to the Bronze Age in Egypt and Mesopotamia (c. 3000–1200 BCE). Their contributions to mathematics, astronomy, and medicine entered and shaped the Greek natural philosophy of classical antiquity and later medieval scholarship, whereby formal attempts were made to provide explanations of events in the physical world based on natural causes; while further advances, including the introduction of the Hindu–Arabic numeral system, were made during the Golden Age of India and Islamic Golden Age.

The recovery and assimilation of Greek works and Islamic inquiries into Western Europe during the Renaissance revived natural philosophy, which was later transformed by the Scientific Revolution that began in the 16th century as new ideas and discoveries departed from previous Greek conceptions and traditions. The scientific method soon played a greater role in the acquisition of knowledge, and in the 19th century, many of the institutional and professional features of science began to take shape, along with the changing of "natural philosophy" to "natural science".

New knowledge in science is advanced by research from scientists who are motivated by curiosity about the world and a desire to solve problems. Contemporary scientific research is often highly collaborative and is frequently carried out by teams in academic and research institutions, government agencies, and companies. At the same time, many major advances—particularly in fundamental science—have come from individual researchers and are widely recognised through major international awards such as the Nobel Prize. The practical results of scientific work have led to the emergence of science policies that seek to prioritise the responsible development of commercial products, health care, public infrastructure, environmental protection, and defense capabilities. (Full article...)