Notification Bar Simple
Use simple notifications for generic content that does not fit the other available categories.
Notification Bar Reminder
Use reminder notifications for reminding alerts to the user.
Notification Bar Error
Use error notifications whenever there are errors occuring, whether as a result of server malfunctions or of invalid user input. When using this notification together with form validation, only show it after the user has actively submitted the respective form.
Notification Bar Info
Use informational notifications whenever you can provide context relevant additional information to the user.