There is a field in the shopping cart that allows your purchaser to type a message to you, the seller.  This can be useful for special cases, providing additional shipping information, to let you know it's a gift or a myriad of other uses.

Here's what the customer sees in the shopping cart (after clicking on the Go to Checkout button):

Here's what the receipt to you,the site owner, looks like:

Here's what the receipt to the customer looks like:

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