Annotations serve the purpose of conveying metadata about the

class to its consumers without creating a separate type for it.

Annotations are more powerful than a Marker interface. They allow

programmers to pass more sophisticated information to classes that

"consume" it.

https://www.javacodegeeks.com/2012/10/is-there-a-better-approach-to-marker.html#:~:text=It%20seems%20annotation%20is%20a,subclasses%20of%20the%20marked%20class.