telephone

Device that coverts sound and electrical waves into audible relays, and is used for communication. 

The telephone consists of two essential parts; a microphone and a speaker. 

This allows the user to speak into the device and also hear transmissions from the other user. 

The invention of the first telephone dates back to 1896. 

Some of the first telephones required an operator to connect calls between users, but with the advancement of technology, calls are now connected automatically. 

Telephones formally utilized analog signals to transmit sounds, but most calls are now placed over digital networks. 

Telephones are made in a variety of forms, including a subset of the device called a cell phone or mobile phone. 

Also called phone.

audible:聞こえる、音を立てている、可聴式の

relay:交代、リレー、中継、継電器、交代者、新手、換え馬