How we found out how the world works — and how you can check for yourself.
Science is not a pile of facts; it is a method for being less wrong. You make a guess, test it against the world, and change your mind when the evidence says so. This guide covers the big ideas — atoms, cells, evolution, energy, space — and the people who uncovered them.
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6 short chapters in plain language.
Science starts with a question and a testable guess, called a hypothesis. You design an experiment that could prove you wrong, collect data and share it so others can repeat it. A theory in science is not a hunch — it is an explanation that has survived a huge amount of testing.
12 questions with explanations — and an AI tutor if you slip.