diff --git a/csharp_fundamentals/5_working_with_reference_types_and_value_types.md b/csharp_fundamentals/5_working_with_reference_types_and_value_types.md
index 57fc012..91d5f02 100644
--- a/csharp_fundamentals/5_working_with_reference_types_and_value_types.md
+++ b/csharp_fundamentals/5_working_with_reference_types_and_value_types.md
@@ -94,4 +94,8 @@ Differentiate btw Value & Reference:
 
 How to check whether it's reference or value type:
 * Place cursor in VSCode to type, Press `F12`, we can see metadata for the type. It will show whether it's `struct` or `class`
-* The only exception is `String`, it's a reference type but often behave like a value type (i.e. passed as value in function by default)
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+* The only exception is `String`, it's a reference type but often behave like a value type (i.e. passed as value in function by default)
+
+## Taking Advantage of Garbage Collection
+
+.NET runtime provide Garbage Collection service: keep track of objects created, recycle memeory by itself when nothing reference the obj.
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