In the beginning of 20th century,the electronics was used only in the field of telephony and telegraphy.It required a pair of conducting wires.But these days we have cordless telephones,mobile phones which send or receive information without the use of any wire.Such a communication is known as wireless communication.It is possible to have live video conference from anywhere on the earth or in fact millions of kilometers in space.Several space agencies in the world like NASA and ISRO have been using wireless communication on control satallites position controlling digital cameras to take picture and send them back to the earth.
   These days,the radio and television provides a means of communication,education and entertainment.The electronics gadgets like HiFi stereos,CD-player,DVD-player,MP3-player,video games are widely used for entertainment.The use of ICs(integrated circuits)have reduced the size and cost,improved the reliability and performance of the electronic equipment.
   We have the digital cameras and digital camcorders where the picture can be stored on memory stick (flash memory).The picture can be downloaded to a computer to keep a record in albums for sharing with the relatives and friends through the internet.The MP3-player can be used to download the music from the internet and listen at your convenience.