difference between email alert and outbound messages in workflow rule?

here are ome key differences between email alerts and outbound messages:

• Email alerts are sent to email addresses, while outbound messages are sent to external systems.
• Email alerts contain custom messages, while outbound messages contain data in a specific format (such as XML or JSON).
• Email alerts are sent immediately when the workflow rule is triggered, while outbound messages are sent asynchronously (meaning they may not be sent immediately).