Properties are used to define the data for an Item;
Attributes are meta-data for the Item or Property, which are used to control the server logic and Methods.
Think of attributes like command line switches, or as arguments to a function.
In addition to the type, id, and action attributes mentioned below there are several
additional attributes used to control the server. The following is the attribute
reference for the <Item> tag:
Ex 1:
<Item action="add" type="Part">
    <item_number>1234</item_number> 
    <description>welcome to new part</description>
  </Item>
Ex 2:
  <Item action="get" type="Part" id="1234">
  </Item>
Properties : item_number, description
Attributes: action,type, id