The 'CC' in email stands for 'Carbon Copy'.
Why it is true
It is a direct reference to carbon paper, which was used in typewriters to make an instant duplicate of a physical document.
Source: Technology History
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.