Here's an excerpt from a 2016 article at HowToGeek.com that is important information for anyone who does mass emailings.
What BCC Is, and Why You’re a Terrible Person If You Don’t Use It
Few amenities in the modern digital workflow are so widely available but so
widely ignored as the the email BCC function. If you’re guilty of misusing or
neglecting its power (and there’s a good chance you are), it’s time to repent
and, in the process, cut down on spam and protect the privacy of your
neighbors, friends and family.
What Is BCC and Where Did It Come From?
There are three address slots in every email client: TO, CC, and BCC, which
stand for “[deliver] to”, “carbon copy”, and “blind carbon copy”,
respectively. These denotations are a holdover from the world that
preceded electronic mail: physical letters and memos.
Why is the BCC function so important? It allows you to send an email to
someone without that person seeing everyone else that receives the email,
effectively safeguarding their private information.
Now, you may be asking yourself “So what? What does it matter?” It matters for
several reasons. First and foremost, there is the simple issue of privacy and
treating the privacy of the people on your contact list (be they friends,
family, or neighbors) respectfully. It goes without saying that the people who
fire off forwards and mass emails with dozens of their friends and associates
do not take the time to personally contact each of those dozens of recipients
and ask if they would like their contact information shared with everyone else
on the addressee list. It’s outright disrespectful to share contact
information without the permission of the individual in question.
It becomes even more disrespectful and troublesome the more diverse the crowd
of people you’re email is. If you’re emailing ten people in a small civic
organization that already know each other, the issue might be moot. If you’re
a teacher and you’re emailing dozens (if not hundreds) of students some
supplemental material, suddenly you’re sharing the personal contact
information of a lot of people with a lot of other people they may not wish to
share with.
Worse yet, if anyone accidentally hits “Reply All” to any of the emails you
send out with fully loaded TO and CC slots, every single person on the
original recipient list receives the reply. At best, that’s relatively
harmless but certainly wastes the time of everyone else as they open the email
to see what’s new in the discussion. At worst, as has happened many times in
corporations across the world, the email can take on a life of its own as
hundreds of employees reply, argue, and otherwise interact with the email.
Such a reply-all chain reactions can span thousands of emails.
Second, and of more practical concern to those of you that could care less
about good email etiquette and protecting your friends’ privacy, these kind of
bulk emails inadvertently create neat little lists of email addresses for
malicious software and spammers to harvest. If your email address ends up on a
huge email forward sent around the proverbial world, you can rest assured that
somewhere along the line you’ll end up on a spam list. Worse yet, if one of
the users who ends up with your forwarded email sitting in the bowels of their
inbox ends up hit by malware that replicates via contact lists and email
addresses found in the inbox, you’ll likely end up with a malicious email
finding its way to you.
Using BCC Wisely
If you’re in the latter camp, those who ignore the BCC function, you’re likely
asking yourself what you can do to avoid the privacy and security faux pas
outlined above. Don’t worry, once you’re aware how terrible it is to ignore
the BCC function, it becomes readily apparent what you need to do to wash
yourself of your previous poor email behaviors.
When you find yourself with a legitimate reason to email a whole lot of people
at one time. Like, for example, you’re switching to a new email provider or
you want to send your new mailing address to a hundred of your friends and
relatives, the only appropriate thing to do is to put their addresses in the
BCC slot. This ensures that all the evils of mass TO/CC emailing are
eliminated: the email addresses of all the recipients are kept private, there
is no chance of a spam bot or piece of malware on one recipient’s computer
harvesting the email of another recipient, and if any of them need to reply to
you to ask a question or such, they won’t blast out their question or comment
to every other person.
BCC increases privacy, increases security, and cuts down on the inbox crud
your friends and associates have to wade through. There’s absolutely no reason
to avoid using it when doing so is as simple as putting the addresses in a
different address slot.
Thanks for reading and putting this information to good use.
Computer Technology Club, Inc. – Executive Board Minutes
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