What is science? More specifically, what makes something science? How is science distinguished from non-science or pseudoscience?

Nature of science

What is science? More specifically, what makes something science? How is science distinguished from non-science or pseudoscience?

These questions have been the source of debate for many centuries, even millennia. Two thousand years ago, natural philosophers disputed the very nature of matter. Was matter continuous, infinite, and divisible as claimed by Plato, Aristotle, and their contemporaries? Or was matter discontinuous, finite, and indivisible, so that a certain smallest, most fundamental unit could be attained, as claimed by Leucippus, Democritus, and few others. Over 2000 years ago, Leucippus coined a term for this fundamental and smallest unit of matter – atomos, yet these ideas were largely ignored for millennia.

What makes one statement or claim science? Along these lines, how do you distinguish a scientific claim from a non-scientific claim, or pseudoscience?