Do you ever wonder why you are asked to turn off mobile phones and electronic games in an aircraft or hospital, where there are other electrical and electronic systems upon which many people's lives may depend?
Is your favourite radio programme interrupted by interference or the TV screen covered in 'snow' when someone uses a vacuum cleaner or electric drill nearby? Most of the older generation will still remember such problems, even if today (thanks in part to IEC International Standards) they have largely been overcome.
Today interference on your smart phone may even include devices ceasing to work together.
Examples like these illustrate what is called electromagnetic compatibility (EMC).