Most email clients (including Microsoft Outlook, Mozilla Thunderbird, Pegasus Mail...) give you the ability to send a single email to a large number of recipients while concealing the identity of each of the involved contacts. This is done by simply entering the list of recipients into the BCC (blind carbon copy) field instead of using the To or CC (carbon copy) fields.
Enable BCC in Outlook
The Bcc field is not always displayed in the message composition window. To enable this field in Outlook, simply open a new message window and click on Options. Go to the Show Fields section and click on Bcc.
The BCC field can be used to prevent unwanted diffusion of e-mail addresses and thus help to protect the privacy of your contacts.
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