The idea of the atom as the building block of matter has developed over time. What was thought of as a single particle about 1 × 10‾¹⁰ m across is now known to be a collection of smaller particles.

Simple physics may explain how the Easter Island statues could "walk" miles with only a handful of people, but the debate over their transport is far from over.

Atoms are very small. They have a radius of around 1 × 10-10 metres.