Why address an email message to 10 people when you can address it to one? If you often send email messages to a group of of people — like your Friends group, trustees, or colleagues who serve on a committee — you can save time by creating a distribution list from your Outlook contacts or Global Address Book.
A distribution list is a group of e-mail addresses that you create and add to your Outlook contacts as a single e-mail address. When you send a message to a distribution list, it goes to every e-mail address in the list.
You can use the distribution list just like any other email address when composing your message. The name of the distribution can be put in the To:, Cc: or Bcc fields. The name you assign to a distribution list does not display when the recipients get their email message; recipients will just see the full listing of all the names in the distribution list. From their perspective, they don't even know you're using a distribution list!
Note: if you want to prevent recipients from seeing the names and email addresses of everyone else on a distribution list, use the Bcc (Blind Carbon Copy) field to address your message. Here's details on how to activate the Bcc field in Outlook.
Just follow the steps at Microsoft's Create and Edit a Distribution List, or watch this 6-minute video to see how easy it is to create a distribution list in Outlook 2007. (If you use Outlook 2003 you can use Save Time With Distribution Lists in Outlook 2003 instead.)