Errors

A data error is an unwanted change to the data in some way.

Another common way to describe this is to say the data is "corrupt".

Errors happen because 'noise' changes the original data. Noise is a term for any unwanted disturbance in the 'transmission channel'.

For example imagine you are trying to tell something to your friend over the road on a busy street. You shout the best you can, but the trafic 'noise' stops some of your words getting through properly. In this case the 'channel' is the air between you and your friend. The 'noise' is the extra sound being created by traffic.

Now move over to an electrical channel such as a wire or a radio link. In this case the 'noise' is electrical interference caused by things such as lighting or local machinery causing electrical noise. The effect is just the same as a busy street - not all the data gets through in one piece.

To help with this problem error correction and error detection methods have been developed.

2020-10