At times you might want to give a discount over and above Promotional, Qty (quantity) and Season discounts. For this use the "Extra Discount" checkbox on the right before you close the sale. This type of discount applies to the subtotal obtained after factoring in other discounts & sale tax.

Select the 'Extra Discount' checkbox and enter the amount of Extra Discount.  You may also use percentage and then click the 'Convert' button to convert it into an absolute amount.  See illustration below.

If you have not entered an amount for Extra Discount field and you click 'Due' button, the system will prompt you to input a figure because it needs to factor this in to compute the total amount due shown as 'Total : ... " on the right of the 'Due' button.

   Item Discount

Item discount is a discount that you can apply on an item during sale. As shown below, you select the "Item Discount' checkbox to open up the 'Discount' box. You can enter either an absolute value or percentage based on the option button selected. For the same sale receipt, once you apply a discount to an item, the subsequent same item will automatically get the same discount.  (Discount as such will always be shown at the end of the sale receipt.)

For example if you apply 10% item discount on a blouse, then the next same blouse that is transacted for the sale receipt will get 10% off.  However if you did not apply any item discount on the first blouse, any subsequent same blouse will get no discount even if you attempt to apply item discount on it.

Item discount will supercede any promotion discount that had been preset during Add Stock.
 

A question may arise: What if I wish to give a discount on an item for a single instance only.  This can be done by using the 'Manual Entry' mode. However this method has the disadvantage of not logging the sold item barcode and thus reducing the accuracy of your sale reports.