You can group contacts together under a single name or label, so that you can email all contacts in a single step. This is similar to creating a distribution list in other email applications such as Outlook.
To create a contact group or label:
View your contacts by clicking on the App Launcher button near the top-right corner of the screen
Choose Contacts
Position the mouse over the first contact you wish to add to the new group, then click on the checkbox displayed
Click on each additional contact you wish to add to the group
Click on the Labels button along the top of the screen - in the following screenshot, this is the second button from the left
Choose Create Label from the drop-down list
Enter a name for the contact group and click on OK
The label will be created and the contacts assigned to the group.
A single contact can be part of as many groups as required. To add a contact to an existing label:
Position the mouse over the contact you wish to add to a label, then click on the checkbox displayed
Click on the Labels button along the top of the screen
Choose the label you wish to add the selected contact to