Whether we know it or not, we encounter all kinds of electromagnetic waves daily. Some of these come from the microwave, sun, radio, and even at the doctor's office. Most are harmless, but if you're around some of them for too long, damage can be done to our bodies. Let's discuss what an electromagnetic wave is first.
Electromagnetic waves don't need molecules to travel, like sound does. That means they can travel on Earth, through solid objects, and in space. These waves form when an electric field (red) couples with a magnetic field (blue). We can actually see only one form of an electromagnetic wave, while the rest is invisible to the naked eye.
Waves differ in size and energy. The shorter the wavelength, the higher the energy. X-rays are only the size of water molecules, but are very powerful. Maybe you go to the dentist and they give you the lead vest to wear while getting x-rays taken. That's because lead absorbs the harmful x-rays, although they can pass through practically any other solid object. We see visible electromagnetic waves in the form of colors and light. It's wavelength though, is only the size of bacteria. Microwaves are used inside a (you guessed it) microwave oven. Doppler radars that meteorologists use on TV also use microwaves to determine precipitation. Their wavelength is about the size of a baseball. Radio waves can be as large as the size of a building. Thank goodness we can't see those!
Electromagnetic waves are important to most everyday activities. When you're out and about or simply at home, think about all the types of waves you may be experiencing.