Point-of-Sale and iPads have been replacing cash registers steadily over the last few years.
While cash registers are quickly becoming obsolete, odds are you can still find one at your local cash-only artisanal cocktail bar.
Early mechanical registers were entirely mechanical, without receipts. The employee was required to ring up every transaction on the register, and when the total key was pushed, the drawer opened and a bell would ring, alerting the manager to a sale taking place.
Those original machines were nothing but simple adding machines.