The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. There are 7 regions in the electromagnetic spectrum and they are gamma rays, x-rays, ultraviolet, visible light, infrared, microwaves and radio waves. All types of electromagnetic radiation are transverse waves and they all travel at the same speed in a vacuum. The regions of the electromagnetic spectrum are explained below in order of increasing wavelength and decreasing frequency.
Gamma Rays (γ-rays)
Gamma rays have the lowest wavelength but the highest frequency in the electromagnetic spectrum. They are produced by radioactive atoms in nuclear explosions. Gamma rays are highly penetrating rays and can kill living cells, which due to this it is used in medicine to kill cancerous cells. However, they can also kill healthy cells which could lead to cancer. Gamma rays are also used to kill bacteria in food and to sterilise surgical instruments.
X-rays
X-rays are used to produce photographs of bones to check if for any damages or fractures. They can also be used to check metal components and welds or any other damage. The earths atmosphere is too thick for x-rays to enter, so x-ray astronomy has to be done in space. X-rays come from fast electrons that decelerate after striking something.
Advantages of x-rays are they can be used to check if anyone has any broken bones in their body. Disadvantages are that x-rays can cause mutations in the DNA, they can cause cancer and they can cause cell damage by making blood cells have a higher amount of hydrogen peroxide.

Ultraviolet
Ultraviolet is found in sunlight and it can help stimulate the production of vitamin D in the skin. There are many benefits that ultraviolet have, such as it promotes vitamin d which helps with bone growth and for normal functioning of the nervous system. However, ultraviolet also has harmful effects such as it can cause skin cancer. Ultraviolet is used in fluorescent lamps and to detect fake banknotes and credit cards.
Ultraviolet is also used in sunbeds give people a tan quicker when they lay in the bed. Ultraviolet was discovered by Johann Ritter. He discover it by using silver chloride and exposing it to the light at the violet end of the spectrum. Silver chloride turns black when exposed to light and it turned black the fastest when placed near the violet end of the spectrum.
Visible Light
Visible light is the only electromagnetic radiation that is visible to the human eye. We see visible light by the light focusing onto the retina of the eye which creates a visual image in the brain. Visible light is also an essential energy source for plants because they need it when they undergo photosynthesis. Visible light is used in many things such as photography, illumination and also our vision.
Infrared
infrared comes from heat or thermal radiation and it is produced by the motion of atoms and molecules in an object. infrared is used for heating and cooking and also in thermal imaging devices. Infrared was discovered by a british astronomer called William Herschel. He discovered infrared by using a prism to break up visible light, then he realised that the temperature rose from violet to red (using a thermometer) and then where there was no visible light at the red end of the spectrum, the temperature was the highest. Which this is how he discovered infrared. An advantage of infrared is it can be used to detect people, which it is used by the police to find criminals from a helicopter when they are trying to escape. Also, infrared can be used for many things such as tv remote controls, security systems, short range communication and optical fibres. A drawback of infrared is it can cause skin burns.
Microwaves
Microwaves are used for many things such as radar technology, microwave ovens, mobile phone and satellite communications. Microwaves are used in microwave ovens by vibrating the water molecules at microwave frequency. A benefit of microwaves is that it can be used to transmit signals which they are used on all mobile phones. A drawback of microwave radiation is that it can cause internal bleeding of body tissues.
Radio Waves
Radio waves have the lowest frequency and the longest wavelength in the electromagnetic spectrum. Natural radio waves are made by lightning, but artificially generated radio waves are used radio communication, broadcasting, radar and many other navigation systems. Advantages of radio waves is they can travel over a large distance due to their high wavelength. A Disadvantage of radio waves is they can be disrupted really easily from things like storms.