From the Memory Variables window you can you can:
Add a new memory variable
Delete a memory variable
Modify a memory variable
Adding, modifying or deleting the memory variables:
Right-click a memory variable to display a drop-down list. Choose one of the following:
New – the New Memory Variable window displays. Refer to “Adding memory variables”.)
Properties – the Memory Variable Properties window displays. You can modify the memory variable you right-clicked. See the procedure, “Modifying memory variables”.
Delete – you are asked to confirm that you want to permanently remove the memory variable you right-clicked.