To create a new variable, we will click on the big + icon in the Variables dialog window. The Create Variable dialog window will open.

The declaration is rather simple. We have to provide the name and select the variable type. We have three choices: Type, Message Type, and Element. We select Type for the simple XML Schema types. We select Message Type for the WSDL MessageTypes. We select Element for XML element variables.

Let's declare the BookstoreLocationWithLowestStockQuantity variable. This variable will be of the type string. We will enter the variable Name, select Type for the type, and use the magnifier glass icon to select a string from XML Schema Simple Types:

We could initialize the variable with the default value. This can be achieved in the Initialize tab. We could also enter the detailed description of the variable and its purpose. This can be done in the Documentation tab. We will not use these...