The principles and theories of science have been established through repeated experimentation and observation and have been refereed through peer review before general acceptance by the scientific community. Acceptance does not imply rigidity or constraint, or denote dogma. Instead, as new data become available, previous scientific explanations are revised and improved, or rejected and replaced. Science is a way of making sense of the world, with internally-consistent methods and principles that are well described. There is a progression from a hypothesis to a theory using testable, scientific laws. Only a few scientific facts are natural laws and many hypotheses are tested to generate a theory. Find out how scientific hypotheses, theories and laws describe the natural world.