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+---
+title: Getting Started with DiagnosticSource
+description: A tutorial to create a basic DiagnosticSource and understand key concepts
+ms.date: 05/02/2022
+---
+# Getting Started with DiagnosticSource
+
+**This article applies to: ✔️** .NET Core 3.1 and later versions **✔️** .NET Framework 4.5 and later versions
+
+This walkthrough shows <xref:System.Diagnostics.DiagnosticSource?displayProperty=nameWithType> 
+
+## Log an event
+
+The `DiagnosticSource` type is an abstract base class that defines the methods needed to log events. The class that holds the implementation is `DiagnosticListener`.
+The first step in instrumenting code with `DiagnosticSource` is to create a
+`DiagnosticListener`. For example:
+
+```C#
+    private static DiagnosticSource httpLogger = new DiagnosticListener("System.Net.Http");
+```
+Notice that httpLogger is typed as a `DiagnosticSource`. 
+This is because this code
+only cares about writing events and thus only cares about the  `DiagnosticSource` methods that
+the `DiagnosticListener` implements. `DiagnosticListeners` are given names when they are created
+and this name should be the name of logical grouping of related events (typically the component).
+Later this name is used to find the Listener and subscribe to any of its events. `DiagnosticListeners` have a name, which is used to represent the component associated with the event.
+Thus the event names only need to be unique within a component.