If you could take an apple and break it into smaller and smaller parts, you would find molecules, then atoms, followed by subatomic particles like protons and the quarks and gluons that make them up.

We independently review everything we recommend. When you buy through our links, we may earn a commission. Learn more› By Doug Mahoney Doug Mahoney is a writer covering home-improvement topics, ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Somer G. Anderson is CPA, doctor of ...