Once you've created a Google Contacts label, you can begin using that label to contact members assigned to it.
Using a Google Contacts label is just as easy as using an email address.
Simply type the name of the Google Contact label in either the To:, Cc:, or Bcc: fields of a new email.

Simply type the name of the Google Contacts label in the Guests field of a Google Calendar event.

Simply type the name of the Google Contacts label in the Invite people field of the Sharing settings for a Google Drive file/folder.
