By now you have studied more than half of this course. You may have been to the study centre a few times. You might have taken lessons on audio cassette-recorders and watched video programmes on the television set. You may even have heard some programmes on ther audio. All these gadgets that you have come across, the radio, television, taperecorders, video cassette-players are products of the semiconductiir techilology.
Semiconductors are the basis of all the sophisticated electronics we have today. inistal watches, calculators, aircraft, spacecraft, satellites, telephone exchanges, lasers and dany more devices have components or equipment made up of semiconductors. There is hardly a tool, appliance or item of communication, long distance transportation, entertainment or defence that does not use semiconductor technology. These products and the semiconductors which are used in them have created great impact on many aspects of our social, cultural and economic development.