Always use the Bcc-field when e-mailing people who don't know each other and/or more than 5-10 people at a time.
Put your own address in the To-field, and everyone else in the Bcc-field.
Easy!
Example:
John wants to send an e-mail to 50 of his friends to tell them about his new address and phone number. He puts himself in the to-field, and then everyone else in the Bcc-field.
When his friends get the e-mail, it looks like this:
From: John <john@agreatdomain.com>
To: John <john@agreatdomain.com>
Subject: I'm moving!
Hi guys!
Here's my new address and phone number.
No one who get's the e-mail can see the other people's addresses, and no one can do a clumsy "Reply to all". Everything is safe.
Bad example with To instead of Bcc:
If John had sent the e-mail with everyone in the To-field, this would quickly have gotten ugly, when people start to mistakenly click on "Reply to all" or see an opportunity to send "information".
From: John <john@agreatdomain.com>
To: Lisa, Sara, David, Mike, Al ... (and 45 more people)
Subject: I'm moving!
Hi guys!
Here's my new address and phone number. (...)
From: David
To: John, Lisa, Sara, Mike, Al ... (and 45 more people)
Subject: Re: I'm moving!
Congrats John! That's great, when is the house warming party?
/David
From: Mike
To: John, Lisa, Sara, David, Al ... (and 45 more people)
Subject: Re: I'm moving!
John, nice to hear that you finally moved.
By the way, I'm considering a hair transplant and leaving my wife, could we go for a beer and talk some private stuff some day?
/Mike
From: Sara
To: John, Lisa, David, Mike, Al ... (and 45 more people)
Subject: Re: Re: I'm moving!
FFS! Stop using the Reply to All-button you noobs! I don't want my mailbox full!
/Sara
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To: John, Lisa, Sara, Mike, David, Al ... (and 45 more people)
Subject: Excellent price on our drugs
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