diff --git a/Databases/GraphQL/Key_characteristics_of_GraphQL.md b/Databases/GraphQL/Key_characteristics_of_GraphQL.md
index f2c88f9..a22679d 100644
--- a/Databases/GraphQL/Key_characteristics_of_GraphQL.md
+++ b/Databases/GraphQL/Key_characteristics_of_GraphQL.md
@@ -41,10 +41,14 @@ There is a third request type called a **subscription**. This is used for real-t
 
 ### Structure and behaviour
 
-A schema is strongly typed and is basically a graph of fields that have types, e.g
+We define the structure of a GraphQL API through the schema. A schema is strongly typed and is basically a graph of fields that have types, e.g
 
 ```graphql
 {
   name: String
 }
 ```
+
+We implement the behaviour of the API through functions called **resolver functions**. Each field in a GraphQL schema is backed by a resolver function. A resolver function defines what data to fetch for its field.
+
+> A resolver function represents the instructions on how and where to access raw data. For example, a resolver function might issue a SQL statement to a relational database, read a file’s data directly from the operating system, or update some cached data in a document database. A resolver function is directly related to a field in a GraphQL request, and it can represent a single primitive value, an object, or a list of values or objects.
diff --git a/Software_Engineering/Memory_leaks.md b/Software_Engineering/Memory_leaks.md
index 2d5b947..b694d5e 100644
--- a/Software_Engineering/Memory_leaks.md
+++ b/Software_Engineering/Memory_leaks.md
@@ -7,3 +7,4 @@ tags: [memory]
 # Memory leaks
 
 A memory leak occurs when you program memory and forget to delete it once you are finished. The consequences of memory leak is that it reduces the performance of the computer by reducing the amount of available memory. Eventually, in the worst case, too much of the available memory may become allocated and all or part of the system or device stops working correctly, the application fails, or the system slows down vastly .
+  
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