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  <types>
    <xsd:schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="urn:Hello">
      <xsd:element name="getName" type="xsd:string" />
	  <xsd:element name="HelloResponse" type="xsd:string" />	 	  
	</xsd:schema>			
  </types>

In our practice, we want to pass simple string. So, we write xsd:string. Other, you can use numeric type. For strings or numerics, we can handle with simple way xsd:string or xsd:int which does not get defined here. For objects and arrays, we will talk next time.