what is blind carbon copy in emails?

In the context of correspondence, blind carbon copy(abbreviated Bcc:) refers to the practice of sending a message to multiple recipients in such a way that conceals individual email addresses (mentioned in "to" field of the mail) from the complete list of recipients. In some circumstances, the typist must ensure that multiple recipients of such a document not see the names of other recipients. To achieve this, the typist can:

• Add the names in a second step to each copy, without carbon paper
• Set the ribbon not to strike the paper, which leaves names off the top copy (but may leave letter impressions on the paper)

To specify recipients, an e-mail message may contain addresses in any of these three fields:

• To: Primary recipients
• Cc: Carbon copy to secondary recipients-other interested parties
• Bcc: Blind carbon copy to tertiary recipients who receive the message without anyone else (including the To, Cc, and Bcc recipients) seeing who the tertiary recipients are.

It is common practice to use the Bcc: field when addressing a very long list of recipients, or a list of recipients that should not (necessarily) know each other.