Difference between event and delegate

[asin.pro]

Who can explain me what the difference between DECLARE_EVENT and DECLARE_DYNAMIC_MULTICAST_DELEGATE, I didn’t catch. What is the profit of declare friend class in event scope, if I still can call Broadcast method from any place of code?

[asin.pro]

DOCS: While any class can bind events, only the class that declares the event may invoke the event’s Broadcast, IsBound, and Clear functions. This means event objects can be exposed in a public interface without worrying about giving external classes access to these sensitive functions.
https://docs.unrealengine.com/en-US/…nts/index.html

#define FUNC_DECLARE_EVENT( OwningType, EventName, ... ) \
class EventName : public TBaseMulticastDelegate<__VA_ARGS__> \
{ \
friend class OwningType; \
};

[Emaer]

Events are very similar to multi-cast delegates . However, while any class can bind events, only the class that declares the event may invoke the event’s Broadcast, IsBound, and Clear functions. This means event objects can be exposed in a public interface without worrying about giving external classes access to these sensitive functions. Event use cases include including callbacks in purely abstract classes, and restricting external classes from invoking the Broadcast, IsBound, and Clear functions.

Multi-cast Delegates

[asin.pro]

I’ve found the same question. **zeryzhang, **in his last comment, point out, it’s incomplete design for key functions encapsulation.

[asin.pro]

Actual link is Delegate events does't work?