Ultraviolet light can give you a suntan (or burn), and too much of certain UV frequencies can increase one's risk of skin cancer. Some frequencies are blocked by the Earth's [[ozone layer]].
Even higher frequencies include X-rays and gamma rays.Both are known to be hazardous because of their ability to pass through, and cause damage to, flesh and organs.<ref>http://www.epa.gov/radiation/understand/gamma.html</ref>
More colloquially, the spectrum is simply the range of electromagnetic [[radio]] frequencies used in the transmission of sound, [[data]] and [[television]]. [[Category:Telecommunications]]