Indicates the method used to enter the card's details.
The card was swiped through a Square reader or Square stand.
The card information was keyed manually into Square Point of Sale or a
Square-hosted web form.
The card was processed via EMV with a Square reader.
The buyer's card details were already on file with Square.
The card was processed via a contactless (i.e., NFC) transaction
with a Square reader.