Windows Contacts is a new application in Windows Vista, which is used to store information about people with whom a user regularly communicates. It has replaced the Windows Address Book application that was available with earlier versions of Windows.
Contact group is a collection of contacts made through Windows Contacts. The contact group is used by users to send a single e-mail to multiple users. It saves time and efforts of a user to manually enter e-mail address of each member of the group.
