What communication methods are traditional in society, and what are their shortcomings?

Ancient times: letters, oral messages, flying pigeon handed down books. Features: a slow and vivid sentence: traffic basically depends on walking, and communication basically depends on shouting.

Modern: telegraph, wired telephone, letters, information. It is faster than the ancient means of communication.

Modern: microwave communication satellite communication optical fiber communication features: high speed, low cost, high precision, strong confidentiality, diverse ways and large amount of information.

However, in modern fast-paced life, some people will use traditional communication methods, such as sending postcards to themselves or friends at various tourist attractions or sending letters slowly. The people received were refreshing, literary and unforgettable.