Trade discount: This is granted by the seller to the buyer in order to motivate him to buy in large quantities.
Cash discount: This is granted by the seller to the buyer in order to motivate him to be making cash or prompt payments whenever he buys.
Quantity discount: This is equivalent to trade discount. It is granted to the buyer to encourage him to be buying in bulk.
Cash register: This is a book that is used by retail shops in recording cash sales. It enables the retailer to keep good account of all his business transactions with other people.