Examples of communication Mobile phone=Telephone+SMS+ 圈 Radio+TV+Internet+... SMS(QQ,WeChat)=Short Message Sys =Telegraphy Telegraphy:oldest communication sys Morse code (1837)uses DASH and DOT(0/1),representing long and short pulses respectively,to code a letter in a text. 議 UESTC-Introduction Prof李晓峰 6