Welcome to Physics! I’m ATOM, and I’ll be your guide around here. A gaggle of wacky characters are on hand to explain the building blocks of our universe. Click on my friends to the left to meet them.

Hiya, FREQUENCY here.
I’m the most important measure of any wave. I am the one that counts because I tell you how many cycles—or identical patterns of waves—pass a point in a given time.

I'm GRAVITY.
I am a mystical mover and shaker. A universal fixer, I hold Earth together, keep the planets in their orbits, and make stars form.

Let there be me: LIGHT.
I control what the world looks like because I am what you see when you look at it. Plants use my energy to help them grow. The future’s bright—it’s blindingly obvious!

MAGNETISM
I’m Magnetism. I may not be a fundamental force, but I’m not useless. I’m bipolar, with a strong north-south divide. I’m an integral part of Earth—use me to get your bearings with a compass.

I'm SOUND.
I surround you—no matter where you go, I’m there, vibrating in your ears. Even the quietest sound moves your eardrums. This is a good thing because it lets you talk to other people and listen to the world’s most beautiful noises.

I'm STATIC ELECTRICITY.
People say I’m a useless nuisance. I like to hang around on the surface of things, going nowhere fast. When I move, I’m gone in a flash. As lightning, I kill around 1,000 people per year.

They call me VACUUM.
I’m a riddle. I am what I’m not. A blank space without a crumb of matter. Diddly-squat. Ancient scientists thought that I was impossible—how could nothing be something?

I'm X-RAY
an electromagnet peeping Thom who finds it irresistible to peek inside things. Although I’m dangerous company, my talent for spying makes me useful in medicine and industry—I’m a star with that all-important “x” factor!