ICT

1) Differentiating various communication devices

Past

- Various tribes in Africa used a sound wooden drum to send a                                                                                              message

- The Americans native people used smoke to send the message that can be seen in several miles away

- Before the invention of electronics devices such as telephone, the sending of message
   to the long distance became a simple process

- In the 18th century, the wooden barriers on the high pole in french along the country sending a signal up to hundreds of kilometres away

Modern/Nowadays

-Claude chappe  invented a semaphore system in 1797 and now it still being used by navy to send a message among the ship

- in 1838, an american named Samuel Morse inveted a code in the form of long and short flases of the electric current or lamp.

- Around 1870s, a Scotland Alexander Graham Bell invented a telephone. The working principles of the telephone to change the sound  becoming an electric signal

2. Several devices of ICT

-laptop

-radio

-telephone

-cellphone

-computer