The CC and BCC fields in your email app look similar, but they serve two very different purposes. Confusing the two can sometimes lead to annoying or even embarrassing problems. In this article, we’ll explain everything you need to know about these two methods of sending email, explain the differences between CC and BCC, and show you when each works best.

The terms CC and BCC long predate email. They date back to the days of office-to-office business communications, when a copy of a letter was literally made by inserting a piece of carbon paper between the letter and the original as it was typed on a typewriter. The copy was called a carbon copy, and the top of the letter was often marked with a “cc: Dave Johnson” to indicate to whom the copy was being sent.

With the blind carbon copy, or BCC, the idea of the CC is made invisible. The recipient of the message does not know that the BCC person has also received a copy.

In general, most routine emails should be sent with recipients on the To: and CC: lines. The most relevant recipients, or recipients who need to take action on the email, should be placed on the To line, while informational-only recipients can be placed on the CC line. You may want to CC everyone in situations such as sending a broad communication (such as a newsletter) to a number of people at once.