Radio refers to the wireless transmission of signals through free space by electromagnetic radiation of the frequency that are below of the visible light in the radio frequency range from about 30 kHz to 300 GHz. These waves are called radio waves. The information gathered such as sounds are carried by systematically changing some property of the radiated waves like that of phase, frequency and amplitude or pulse width. The electromagnetic radiation travels by means of oscillating electromagnetic fields that can pass through air and the vacuum of space. The information in the waves are being extracted and transformed back into its original forms.
The word radio or radiotelegraphy is also called as the wireless telegraphy which is shortened by the British into wireless. The prefix radio- is first used in the word radioconductor given by the Edouard Branly a French physicist in the late 1800’s. The term radio is based from the verb “to radiate”. The term radio also appears in the article written by Lee De Forest in the year 1907. The term was adopted by the United States Navy in the year 1912 in order to distinguish radio from other wireless communication technologies like the photophone.
Radio serves as communications and used as a device to pass on orders between the military soldiers. True enough, radios, were even used during the World War I, countries, militaries and officials of allied countries uses radio to give instructions and information to the other. Germany also use radio communications for diplomatic messages just like when they found out that their submarine were trapped by the British.
Broadcasting with the use of radio begun in the year 1909 in San Jose, California and later in the year 1029, there is a widespread introduction of radio receivers in the whole United States and even in Europe.
Today radio serves many purposes and the very important of them all, is that radio serves as means of delivering news even in the most remote places in the world. Before televisions and internets were made, people rely on radio news in order to gather information and to know the happening within the place. Radio news, is said to be accurate and fast. By listening to radio news, you do not need to stop and sit in front of a screen. You can gather information while doing your usual chores. It convenient to listen to radio news, but the downside is that, it cannot give you a picture of what is really happening.