What is a distribution group?
Use Office 365 distribution groups, also called distribution lists, to send emails or meeting requests to multiple people. Distribution groups come in handy for project teams or committees since you can send messages without having to add every email address each time.
You don't need to be an admin to create a distribution group. However, if you want people from outside your organization to become a member of your distribution group, an admin will need to set permissions for those contacts. For external contacts from other domains to become members of a distribution group, the admin must make the external contacts shared contacts.
Microsoft provides Office 365 groups, which contain distribution groups, but also include other group-related collaboration features, including a library for storing and working on group files and folders, a tool for organizing and assigning tasks, and updates on project progress. Learn more about Office 365 Groups from Microsoft.