If you regularly email the same group of people, it’s easy to save a little time by creating an email group. You can do this on the fly while composing an email.
Once you’ve added the recipient names to your mail, click on the To: link to the left of these names:
This opens a dialog via which you can add more recipients if you wish, but which also has a Save as group option near the bottom:
Name the group with something you’ll remember:
In future you can select your group via the To: dialog in order to compose an email to this group of people:
Don’t forget that, once you’ve brought up the list of names by typing the group name, you can then remove individual names (by clicking on the x next to the name) and they’ll be removed from the recipient list for this email but they’ll NOT be removed from the email group, so they’ll still appear in any future emails you send to the group.
Finally, note that all of the above works identically with Cc: and Bcc: as it does with To:, so you can copy or blind-copy to groups too.