When you are writing a business letter, you may need to use a carbon copy, but it's not a literal carbon copy. The abbreviation CC: stands for carbon copy, and here is how you CC: a letter. When you write your letter to someone, you may need the same letter to either go to another person, or for another person to be made aware of the letter. This is a common practice in business, because a secretary might compose a letter to an employee, but send that same letter to three supervisors. What the CC: is is a notification to all parties that someone else received the letter. It is an obligation to inform all parties that someone else saw the document. At the bottom of the letter page, under the signature you will place the abbreviation CC: with a list of names of everyone (other than the addressee) who received a copy of the letter. The tricky part is that in the CC: space you will need to change the names for every draft of the letter.