Wavelength and Frequency:
When the wavelength increases, the frequency decreases. If you think about it, in a certain amount of space to fill, you can either have a few large objects, or many small objects. Same with the waves, the fewer the waves, the larger the wavelength. The more the waves, the smaller the wavelength.
For each wave on the spectrum, there are different wavelengths and frequencies. The spectrum is made up of a series of waves, in order from longest wavelengths to shortest wavelengths.
Radio waves are electromagnetic waves. These have the longest wavelengths and the lowest frequency on the spectrum. Radio waves are used in stereos, radios, and television.
Microwaves are the next on the spectrum. They have a slightly shorter wavelength and a slightly higher frequency. Microwaves are measured using radar(radio detection ranging). They are used in cellular communication.
Infrared waves are the third section on the spectrum. They end in the middle of the visible light scale. They, again, have a slightly lesser wavelength and so on. They are found in electric stoves, heat lamps, and heat sensory devices.
Visible light is the small scale between Infrared and Ultraviolet rays. They have shorter wavelengths and an extremely high frequency. Visible light that appears white is actually a mixture of many colors, being reflected together. As the wavelengths decrease, you can see other colors appear in the spectrum. Obviously, the light spectrum can be seen everywhere.
These have higher frequencies than visible light, so they carry more energy. The energy in ultraviolet rays is enough to kill all living cells, and are often used to kill bacteria on hospital equipment. Although, they can be beneficial, as they are used to produce vitamin D, which is needed for healthier teeth and bones.
X-rays have a higher frequency than ultraviolet rays, and thus carry more energy. enough to penetrate most matter, excluding dense matter such as bone. These matters absorb the rays and allow them to pass through. They can be recorded to produce interior images of bones and tumors.
The final factor on the spectrum, are gamma rays. These have the highest frequency and the lowest wavelength. Often produced by nuclear reactions, they are the most penetrating of all electromagnetic waves. Gamma rays can be used to kill cancer cells inside the body. Objects in space are also known to give off gamma rays, though they are blocked by earth's atmosphere. They can not be measured unless the satellite is in orbit.
Waves in the world
In the spectrum, the waves are extremely beneficial to everyday needs. Often used in medical home uses. They have also been used to further scientific discoveries.