ash) An earlier symbol for Bitcoin Cash (BCH). See Bitcoin Cash
opy) The field in an email message that names additional recipients but keeps their names hidden. Written as bcc: (with a colon), it is used to send or forward a message to one or more people without divulging their addresses.
In contrast, the regular cc: shows all the recipients' names in the message, which is what many people use without being aware of the bcc: option. Very often, people forward an email to friends, who in turn forward it to others, and without recipients added as a bcc:, everybody sees everybody else's email address.
A Potential Spam Generator
Messages with many bcc: recipients may be tagged as spam, because spammers may use blind carbon copy addresses. Mailing list software is an alternative that sends individual messages to a list of addresses. See mailing list software
The Carbon Copy
The carbon copy term comes from carbon paper, which was a sheet of ink inserted between two sheets of paper to make a copy in a typewriter. The bcc: and cc: are making copies of a message to additional recipients. See fcc
Blind Carbon Copy
In this mail program, all the addresses in the bcc line will be sent the message, but nobody will know who else got it.
Carbon Paper Makes Typewriter Copies
This is a French typewriter with the AZERTY keyboard and not the common QWERTY keyboard (see QWERTY keyboard