If the feature is activated through Configuration, notifications and alerts can be accessed from the title bar and optionally sent by email when certain events occur. Here you can determine the events that cause notifications for members of this login group. You can copy settings from another group, can check listed entries and then choose to remove them or add and select required events.
The notifications to be received will generally depend on whether users are managers (and so need to know the actions of subordinates), team members (when something is assigned) or a project manager (something is overdue).
Check Allow Opt-In Email Notifications if individual users can choose, through the My Email Notifications, the events for which they receive notifications. If unchecked, all users in the Login Group must receive the indicated notifications.