Data Transmission

Data transmission refer to the movement of data in form of bits between two or more digital devices. This transfer of data takes place via some form of transmission media.

Serial data transmission
In serial data transmission,  data is transmitted as a single bit at a time using a fixed time interval for each bit. The various bits of data are transmitted serially one after the other.

The data must pass through a serial interface to exit a computer as a serial data. This communication is also called a one-at-a-time transmission because bits are transferred one after each other.

Parallel data transmission

In parallel transmission, multiple bits are transmitted across multiple transmission lines. Many data bits or multiple byte are also transferred per clock cycle.

During this transmission, there are multiple wires connecting each sub-unit and data is exchanged using a parallel transfer mode. This mode of operation results in minimal delays in transferring each word. Parallel transmission is used for short distance communication.

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