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Q. Most people no longer use a typewriter and carbon paper when making a copy of a letter. Does that mean that “cc” should now be just “c”?
A. Not necessarily. In language, it’s common for conventions to outlive their original meanings. We still talk about a “dial tone,” for instance, even though very few of us have dials on our phones. The convention is to write “cc,” so I would continue to do that.