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In our increasingly connected digital world data communication is the lifeblood that connects us. Understanding how different methods of data transmission work is vital for designing reliable and efficient networks. From the one-way simplicity of simplex communication to the bidirectional nature that is full-duplex communications, different methods dictate how data is transmitted and received.
To transfer data efficiently hardware in a communication circuit will use various techniques, including multiplexing as well as demultiplexing, which are processes that combine and separate signals into single composite ones for transmission, and then back into individual components. This increases bandwidth and reduces costs. Signal amplifiers and error-detecting codes minimize data corruption due to electrical or mechanical disturbances.
Data communications also have an array (protocol) of rules that are followed by the computers used by the sender and the receiver. These rules help ensure that the message is understood and accepted without error.
The sender is the computer or device that creates and sends out the message, which could be in the form of numbers, text images, sound or video. The receiver is the computer or device that receives the message which may be the same as the sender, or different. The transmission medium is the physical path from the sender to the receiver. It could be a wired medium, such as twisted pair wire fiber optic cable, or wireless like microwaves, or radio waves.