The radio can be defined as the process of sending and receiving messages, etc. by electromagnetic waves without connecting a wire. It refers to a device which broadcasts messages, news, notices, songs etc. by means of electromagnetic waves. The radio is the cheapest and most common means used for getting knowledge, information and entertainment. It was invented by an Italian scientist Marconi in 1902. Nowadays too, it is widely used all over the world.

The radio is very useful for us. It gives us news quickly. We can learn what is happened in the world by listening to the radio. Everybody wants to have a radio set. It quickly broadcast national and international news. Thus it keeps us in touch with all the parts of the world. Radio stations broadcast different types of programmes. We can listen to the weather report. Similarly many knowledgeous programmes are broadcast through radios. The programmes related to health, food, physical exercise, language, religion, philosophy etc. are knowledgeous for everyone.