Data communication is the transfer of data from one place to another through a network. This may be a wired medium, such as optical fibers or copper wires, a wireless medium like microwaves or radio waves, or even a computer bus. The information transferred is typically represented by an electromagnetic signal which may vary in amplitude or speed.

In data communication, the most difficult task is transmitting information over long distances. This is because signals that travel through long conductors are susceptible to noise or electrical distortion which can alter the original information.

Error detection plays a crucial role in the successful communication of data. This is achieved by adding a checksum to the data packets which make up a transmission and comparing it to the sum of all the individual packets as they reach their destination. If the sum that is derived is zero, then there were no errors have occurred data communication in the data transmission.

It is crucial to maintain a high transmission rate for an accurate and reliable transmission. This can be achieved either by ensuring the data transfers on a medium without interference or by sending redundant data to prevent the loss that is caused by interruptions in a moment.

Data communication that is efficient is essential for many applications, such as chat, traffic information downloads, file downloads and other internet-based services. For instance, traffic information communicates real-time estimations of traffic speed to passengers and drivers in vehicles on roads, which will help them to make more informed decisions regarding their journey.