What is the difference between C# delegates and events?

In C#, both delegates and events allow passing methods as parameters, but they have the following key differences:

1. Usage: When using delegates, methods can be directly called by invoking the delegate. However, when using events, methods must be called through an event handler.
2. Access restrictions: Delegates can be public, private, or protected, allowing them to be accessed both inside and outside the class. On the other hand, events can only be accessed within the class, with external code calling event handlers through event triggers.
3. Multicasting: Delegates allow multiple methods to be associated with one delegate instance, allowing multiple methods to be executed with one call. In contrast, events only allow one event handler to be associated and trigger the execution of only one method.
4. Security: Events can provide better security by preventing external code from triggering events and only allowing events to be called through the exposed public interface.

In summary, delegates are suitable for situations that require direct method invocation or multicast capabilities, while events are more suitable for situations that require better security and can only be triggered internally.