Error detection is the detection of errors caused by noise or other impairments during transmission from the transmitter to the receiver.
Error correction is the detection of errors and reconstruction of the original, error-free data.
Whenever a message is transmitted, it may get scrambled by noise or data may get corrupted. To avoid this, we use error-detecting codes which are additional data added to a given digital message to help us detect if an error occurred during transmission of the message. A simple example of error-detecting code is parity check.
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