The sun is coming back north, and northerners starved for light and heat should be cheering for electromagnetic radiation. In fact radiation, like fire, confers benefits far greater than its undeniable dangers. Electromagnetic radiation includes X-rays and the dangerous gamma rays released by atomic reactions, but radio waves, television broadcasts, microwaves in and out of ovens, heat radiation and sunlight are also examples. This type of radiation is the only possible way of transmitting energy through a vacuum, and life as we know it could not exist without it. If the Earth could not radiate energy away into the near-vacuum of space, heat from radioactive elements would build up until the planet melted.
Electromagnetic energy exists as waves, with an extremely wide range of wavelengths.
Gamma rays, which are produced by atomic decay, have the shortest wavelengths. Fortunately, the atmosphere does a good job of protecting us from the small amounts of short ultraviolet and X-ray energy put out by the sun. The longest wavelengths in this range are used for long-range communications and navigation aids. Intermediate wavelengths are used for radio and television broadcasts, two-way radio communications, and some radars. Objects at ordinary Earth temperatures emit infrared, and this is how the earth radiates surplus energy to space.