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# C# Delegates and Events Explained with Practical Examples
Delegates and events are important parts of C#. They are especially useful when one component needs to notify another component without tightly coupling the two.
## What is a delegate?
A delegate is a type-safe reference to a method.
```csharp
public delegate void MessageHandler(string message);
static void PrintMessage(string message)
{
Console.WriteLine(message);
}
MessageHandler handler = PrintMessage;
handler("Hello from C#");
```
The delegate describes the method signature that can be assigned to it.
## Multicast delegates
A delegate can reference multiple compatible methods using `+=`.
```csharp
handler += AnotherMessage;
handler("Hello");
```
All subscribed methods are invoked in sequence.
## What is an event?
An event provides a controlled notification mechanism. A class can raise an event while external code can subscribe or unsubscribe.
```csharp
public event EventHandler? Completed;
protected virtual void OnCompleted()
{
Completed?.Invoke(this, EventArgs.Empty);
}
```
## Delegate vs event
A delegate can be invoked directly by code that has access to it. An event restricts invocation so that the declaring type controls when the notification is raised.
## Practical use cases
Delegates and events are common in UI programming, domain notifications, progress reporting, and component communication.
## Summary
Delegates provide type-safe method references, while events build a notification pattern around delegates. Use them when they make communication between components clearer without introducing unnecessary coupling.
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