Hello friend!
There are three possible ways of data exchange.
1. Simplex: data is transmitted in one direction only. this means one end will always be a transmitter and the other end will always be a reciever.
2. Half-Duplex: data is permitted to flow in either direction, but not silmultaneously. At a given time, the transmission can take place only in one direction.
3. Full-duplex: A transmission system in which data can be transmitted in both directions simultaneously.
Hope to help you!