A cash register (US English) or till (British English) is a
mechanical or electronic device for calculating and recording
sales transactions, and an attached cash drawer for storing
cash. The cash register also usually prints a receipt for the
customer. In most cases the drawer can be opened only after a
sale, except when using a special keys, which only senior
employees and the owner have. This reduces the risk of employees
stealing from the shop owner by not recording a sale and
pocketing the money, when a customer does not need a receipt but
has to be given change (cash is more easily checked against
recorded sales than inventory). In fact, cash registers were
first invented for the purpose of eliminating employee theft or
embezzlement, and their original name was the Incorruptible
Cashier. It has also been suggested that odd pricing came about
because by charging odd amounts like 49 or 99 cents, the cashier
very probably had to open the till for the penny change and thus
announce the sale. In the form of