Do you get emails with the address of every other recipient showing? Do you find that as you scroll down there are other lists of other people who sent the email?

You can stop it happening and clear up the mess as well. It’s quite easy.

Let’s assume that you have received an email and want to pass it on to 20 other people. Press the Forward button to set the email up to send on. At this point you can change anything in the email so you can delete all the information about the other people who have been en route.

If there’s a lot, go to the beginning of the part you want to remove, hold the left mouse button down and pull the mouse down the document. All the text selected will have a black background. When you get to the end, release the mouse button and press the delete key on the keyboard. All the rubbish goes.
Now you want to send the fresh email to your 20 friends. Instead of typing the addresses into the To… box type them into the Bcc… box.

That way the email will be sent to everyone but none of the other address will be displayed.

When you create an email you have an address line where you type in the email address of the recipient. Different email systems have different appearances but generally the line has the word To… next to it.
If you click on the To… it will open up the list of people and addresses you have stored. Also showing will be lines with To–>, Cc–> and Bcc–> (This example comes from Microsoft Outlook). It is the Bcc–> which is of interest here.

If you use the line with To–> to enter all your names each person will get the email and the address of each person will be shown to all the recipients.
It is similar with the Cc–> line. This line is for ‘Carbon copies’ and everyone will see all the addresses.
However if you use the Bcc–> line the addresses will not be shown. This line is for ‘Blind carbon copies’ which is set up precisely for this outcome.

Why should this be important? Two examples of emails I have received might show why.
At the University I received an email from the departmental secretary telling me the date, time and room number of a meeting. The message was about 3 lines long. Because it was sent to about 50 people on a mailing list as a carbon copy I had all the address of these people on my email. The system also repeated this information and the email printed out on 3 pages. All for just 3 lines of information.
I recently received an email from a friend with a warning about a virus. This had been sent to him from someone who worked in the prison service. The email I received had been sent to the whole staff of a prison, been forwarded to another prison and sent to all their staff and then forwarded to a third and the process repeated. This trail was attached to the email sent to me and gave me access to the email addresses of about 150 people. This could have been avoided if Blind carbon copy (Bcc) had been used.