When you are notifying a user of the outcome of an action they have taken, provide visual feedback with a Toast Notification.
Inline notification: Inline notifications appear within content areas as close as possible to the thing that it’s about. It is used for contextual information.
Global Notification: A Global Notification is a message object used for system-level notifications that inform the user about system status such as logging in and background processes like data imports.
Confirmation Modal: The confirmation modal confirms the end result of an action such as Destructive / Irreversible actions / Positive actions.
Here are some examples of other existing design systems: