notes about implicit event grid system topic

Author: brown9804

README.md

@@ -56,6 +56,21 @@ Last updated: 2025-06-06
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+> [!NOTE]
+> Azure Event Grid System Topics are free to create and manage, a System Topic is automatically created and managed by Azure for certain Azure services that emit events. It represents a source of events from an Azure resource (like a Storage Account, Key Vault, or Azure Maps). `You don't need to create or manage the topic yourself, Azure does it for you when you enable event publishing on a supported resource.` <br/>
+> - Emits predefined event types (e.g., Microsoft.Storage.BlobCreated, Microsoft.Resources.ResourceWriteSuccess). <br/>
+> - You can attach event handlers (like Azure Functions, Logic Apps, Webhooks) to respond to these events. <br/>
+> - Works seamlessly with serverless architectures for real-time automation. <br/>
+> For example:
+> Suppose you have a Storage Account and want to trigger a function every time a new blob is uploaded: <br/>
+> - Azure automatically creates a System Topic for the Storage Account.
+> - You subscribe to the BlobCreated event.
+> - When a blob is uploaded, Event Grid routes the event to your Azure Function.
+
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+
 ## Important Considerations for Production Environment
 
 <details>