A narrow notch, groove, or opening, as in a keyway in machinery or a slit for coins in a vending machine. Also: A position in a series, sequence, or hierarchy. (Dictionary of American English, by Houghton Mifflin Harcourt)
Depending on the machine, players insert cash or, in “ticket-in, ticket-out” machines, a paper ticket with a barcode that is read by a slot sensor. The reels then spin and stop to rearrange symbols, and the player earns credits based on the paytable. Modern digital technology has allowed slot manufacturers to introduce innovative bonus rounds and varied video graphics.
Slot receivers typically line up a step or two off the line of scrimmage, allowing them to operate more like running backs on pitch plays, reverses, and end-arounds. In addition, they often play a critical blocking role on running plays that go to the outside and safeties, as well as perform crack back blocks on defensive ends on pass protection.
Because they are generally shorter and faster than outside wide receivers, Slot receivers excel at running precise routes. They can also stretch the defense vertically on deep passes, while still being effective in shorter routes like slants and quick outs. In recent years, Slot receivers have become increasingly important as offenses feature more three-receiver sets. This has led to defenses deploying nickel and dime packages to counter them. As a result, Slot receivers must possess exceptional speed and route-running skills to thrive in the NFL.