A BCC (blind carbon copy; also Bcc) is a copy of an email message sent to a recipient whose email address does not appear in the message.
In the context of correspondence, blind carbon copy (abbreviated Bcc:) refers to the practice of sending a message to multiple recipients in a way that conceals the fact that there may be additional addresses from the complete list of recipients. This concept originally applied to paper correspondence and now also applies to email.
This is in contrast to To and CC recipients, whose addresses do appear in the respective header lines. Every recipient of the message can see all the To and CC recipients, but does not know about BCC recipients.
