Pre-modern: Development of outdoor and tabletop ball games

The origins of pinball are intertwined with the history of many other games. Games played outdoors by rolling balls or stones on a grass course, such as bocce or bowls, eventually evolved into various local ground billiards games played by hitting the balls with sticks and propelling them at targets, often around obstacles. Croquet, golf and pall-mall eventually derived from ground billiards variants.

The evolution of outdoor games finally led to indoor versions that could be played on a table, such as billiards, or on the floor of a pub, like bowling and shuffleboard. The tabletop versions of these games became the ancestors of modern pinball.

Late 18th century: Spring launcher invented

Billard japonais, Alsace, France c. 1750–70. It already has a spring mechanism to propel the ball, 100 years before Montague Redgrave's patent.

In France, during the long 1643–1715 reign of Louis XIV, billiard tables were narrowed, with wooden pins or skittles at one end of the table, and players would shoot balls with a stick or cue from the other end, in a game inspired as much by bowling as billiards. Pins took too long to reset when knocked down, so they were eventually fixed to the table, and holes in the table's bed became the targets. Players could ricochet balls off the pins to achieve the more challenging scorable holes. A standardized version of the game eventually became known as bagatelle.

Somewhere between the 1750s and 1770s, the bagatelle variant Billard japonais, or Japanese billiards in English, was invented in Western Europe, despite its name. Also called Stosspudel, it used thin metal pins and replaced the cue at the player's end of the table with a coiled spring and a plunger. The player shot balls up the inclined playfield toward the scoring targets using this plunger, a device that remains in use in pinball to this day, and the game was also directly ancestral to pachinko.

1869: Spring launchers become mainstream

Patent model for U.S. Patent #115,357

In 1869, British inventor Montague Redgrave settled in the United States and manufactured bagatelle tables in Cincinnati, Ohio. In 1871 Redgrave was granted U.S. Patent #115,357 for his "Improvements in Bagatelle",^[3] another name for the spring launcher that was first introduced in Billard japonais. The game also shrank in size to fit atop a bar or counter. The balls became marbles and the wickets became small metal pins. Redgrave's popularization of the spring launcher and innovations in game design (playfield bells^[4]) are acknowledged as the birth of pinball in its modern form.

1931: Coin operation introduced

An early pinball game without flippers, c. 1932

By the 1930s, manufacturers were producing coin-operated versions of bagatelles, now known as "marble games" or "pin games". The table was under glass and used Montague Redgrave's plunger device to propel the ball into the upper playfield.^[5] In 1931 David Gottlieb's Baffle Ball became the first hit of the coin-operated era. Selling for $17.50, the game dispensed five to seven balls for a penny. The game resonated with people wanting cheap entertainment in the Great Depression-era economy. Most drugstores and taverns in the U.S. operated pinball machines, with many locations quickly recovering the cost of the game. Baffle Ball sold over 50,000 units and established Gottlieb as the first major manufacturer of pinball machines.

In 1932, Gottlieb distributor Raymond Moloney found it hard to obtain more Baffle Ball units to sell. In his frustration he founded Lion Manufacturing to produce a game of his design, Ballyhoo, named after a popular magazine. The game became a smash hit. Its larger playfield and ten pockets made it more challenging than Baffle Ball, selling 50,000 units in 7 months.^[6] Moloney eventually changed the name of his company to Bally to reflect the success of this game. These early machines were relatively small, mechanically simple and designed to sit on a counter or bar top.

1933: Electrification and active bumpers introduced

The 1930s saw major advances in pinball design with the introduction of electrification. Pacific Amusements in Los Angeles, California produced Contact in 1933, which had an electrically powered solenoid to propel the ball out of a bonus hole in the middle of the playfield. Another solenoid rang a bell to reward the player.^[7] Contact's designer, Harry Williams, eventually formed his own company, Williams Manufacturing, in 1944. Other manufacturers quickly followed suit with similar features. Electric lights soon became standard on all pinball games, to attract players.

By the end of 1932, approximately 150 companies manufactured pinball machines, most of them in Chicago, Illinois.^[8] Chicago has been the center of pinball manufacturing ever since. Competition was strong, and by 1934, only 14 companies remained.^[9]

During World War II, all major manufacturers of coin-operated games turned to manufacturing for the war effort. Some, like Williams, bought old games from operators and refurbished them, adding new artwork with a patriotic theme. At the end of the war, a generation of Americans looked for amusement in bars and malt shops, and pinball saw another golden age. Improvements such as the tilt-sensing mechanism and the awarding of free games (replays) appeared.

1947: Flippers introduced

Gottlieb's Humpty Dumpty, introduced in 1947, was the first game to add player-controlled flippers to keep the ball in play longer. The low-power flippers required three pairs around the playfield to get the ball to the top.

Triple Action was the first game to feature just two flippers at the bottom of the playfield. Unlike in modern machines, the flippers faced outwards. These flippers were made more powerful by the addition of a DC (direct current) power supply. These innovations were some of many by designer Steve Kordek.

The first game to feature the familiar dual-inward-facing-flipper design was Gottlieb's Just 21 released in January 1950. However, the flippers were rather far apart to allow for a turret ball shooter at the bottom center of the playfield. Another 1950 Gottlieb game, Spot Bowler, was the first with inward-facing flippers placed close together.^[10]

The post-war era was dominated by Gottlieb. Game designers Wayne Neyens and Ed Krynski, with artist Leroy Parker, produced games that collectors consider some of the best classic pinball machines.

1970s: Solid-state electronics and digital displays introduced

A clear-walled electromechanical pinball machine created by the Pacific Pinball Museum to illustrate the inner workings of a typical pinball machine

The introduction of microprocessors brought pinball into the realm of electronic gaming. The electromechanical relays and scoring reels that drove games in the 1950s and 1960s were replaced in the 1970s with circuit boards and digital displays. The first pinball machine using a microprocessor was Flicker, a prototype made by Bally in 1974. Bally soon followed that up with a solid-state version of Bow and Arrow in the same year with a microprocessor board that would be used in eight other machines until 1978, which included Eight Ball, the machine that held the sales record from 1977 to 1993.^[11] The first solid-state pinball is believed by some to be Mirco Games' The Spirit of '76 (1976),^[12] though the first mainstream solid-state game was Williams' Hot Tip (1977). This new technology led to a boom for Williams and Bally, who attracted more players with games featuring more complex rules, digital sound effects, and speech.

The video game boom of the 1980s signaled the end of the boom for pinball. Arcades replaced rows of pinball machines with video games like 1978's Space Invaders, 1979's Asteroids, 1980's Pac-Man, and 1981's Galaga. These earned significantly greater profits than the pinball machines of the day while simultaneously requiring less maintenance. Bally, Williams, and Gottlieb continued to make pinball machines while also manufacturing video games in much higher numbers. Many of the larger companies were acquired by, or merged with, other companies. Chicago Coin was purchased by the Stern family, who brought the company into the digital era as Stern Enterprises, which closed its doors in the mid-1980s. Bally exited the pinball business in 1988 and sold their assets to Williams, who subsequently used the Bally trademark from then on for about half of their pinball releases.

While the video game craze of the late 1970s and early 1980s dealt a severe blow to pinball revenue, it sparked the industry's creative talents. All companies involved tried to take advantage of the new solid-state technology to improve player appeal of pinball and win back former players from video games. Some of this creativity resulted in landmark designs and features still present today. Some of these include speech, such as Williams' Gorgar; ramps for the ball to travel around, such as Williams' Space Shuttle; "multiball", used on Williams' Firepower; multi-level games like Gottlieb's Black Hole and Williams' Black Knight; and blinking chase lights, as used on Bally's Xenon. Although these novel features did not win back players as the manufacturers had hoped, they changed players' perception of pinball for decades.

1980s and 1990s: Pinball in the digital age

A row of pinball machines at the Pinball Hall of Fame in Las Vegas, Nevada

During the 1980s, pinball manufacturers navigated technology changes while going through changes of ownership and mergers: Gottlieb was sold to Premier Technologies, and Bally merged with Williams. The Video game crash of 1983 made the manufacturers refocus on their pinball sales. A trend started of pinball becoming increasingly elaborate to use more computing resources, following video games. Games in the latter half of the decade such as High Speed started incorporating full soundtracks, elaborate light shows and backbox animations - a radical change from the previous decade's electromechanical games. Although pinball continued to compete with video games in arcades, pinball held a premium niche, since the video games of the time could not reproduce an accurate pinball experience.

By the first years of the 1990s, pinball had made a strong comeback and saw new sales highs. Some new manufacturers entered the field, such as Capcom Pinball and Alvin G. and Company, founded by Alvin Gottlieb, son of David Gottlieb. Gary Stern, the son of Williams co-founder Sam Stern, founded Data East Pinball with funding from Data East Japan.

The games from Williams now dominated the industry, with complicated mechanical devices and more elaborate display and sound systems attracting new players to the game. Licensing popular movies and icons of the day became a staple for pinball, with Bally/Williams' The Addams Family from 1992 hitting a modern sales record of 20,270 machines. Two years later, Williams commemorated this benchmark with a limited edition of 1,000 Addams Family Gold pinball machines, featuring gold-colored trim and updated software with new game features. Other notable popular licenses included Indiana Jones: The Pinball Adventure and Star Trek: The Next Generation. Expanding markets in Europe and Asia helped fuel the revival of interest. Pat Lawlor was a designer, working for Williams until their exit from the industry in 1999. About a year later, Lawlor returned to the industry, starting his own company,^[13] working in conjunction with Stern Pinball to produce new games.

The end of the 1990s saw another downturn in the industry, with Gottlieb, Capcom, and Alvin G. closing by the end of 1996. Data East's pinball division was acquired by Sega and became Sega Pinball in 1994. By 1997, there were two companies left: Sega Pinball and Williams. In 1999, Sega sold their pinball division to Gary Stern (President of Sega Pinball at the time) who called his company Stern Pinball.^[14] By this time, Williams games rarely sold more than 4,000 units. In 1999, Williams attempted to revive sales with the Pinball 2000 line of games, merging a video display into the pinball playfield. The reception was initially good with Revenge from Mars selling well over 6,000 machines, but short of the 10,000-plus production runs for releases just six years earlier. The next Pinball 2000 game, Star Wars Episode I, sold only a little over 3,500 machines. Williams exited the pinball business to focus on making gaming equipment for casinos, which was more profitable. They licensed the rights to reproduce Bally/Williams parts to Illinois Pinball and reproduce full-sized machines to The Pinball Factory. Stern Pinball remained the only manufacturer of original pinball machines until 2013, when Jersey Jack Pinball started shipping The Wizard of Oz. Most members of the design teams for Stern Pinball are former employees of Williams.

Amid the 1990s closures, virtual pinball simulations, marketed on computers and home consoles, had become high enough in quality for serious players to take notice: these video versions of pinball such as Epic Pinball, Full Tilt! Pinball and the Pro Pinball series found marketplace success and lasting fan interest, starting a new trend for realistic pinball simulation. This market existed largely independently from the physical pinball manufacturers, and relied upon original designs instead of licenses until the 2000s.

2000s and beyond: Revival

After most pinball manufacturers' closure in the 1990s, smaller independent manufacturers started appearing in the early 2000s.

In November 2005, The Pinball Factory (TPF) in Melbourne, Australia, announced that they would be producing a new Crocodile Hunter-themed pinball machine under the Bally label. With the death of Steve Irwin, it was announced that the future of this game was uncertain.^[15] In 2006, TPF announced that they would be reproducing two popular 1990s era Williams machines, Medieval Madness and Cactus Canyon.^[16] TPF, however, was unable to make good on its promises to produce new machines, and in October 2010 transferred its Williams Electronics Games licenses as well as its pinball spare parts manufacturing and distribution business to Planetary Pinball Supply Inc, a California distributor of pinball replacement parts.^[17]

In 2006, Illinois pinball company PinBall Manufacturing Inc. produced 178 reproductions of Capcom's Big Bang Bar for the European and US markets.^[18][19]

In 2010, MarsaPlay in Spain manufactured a remake of Inder's original Canasta titled New Canasta,^[20][21] which was the first game to include a liquid-crystal display (LCD) screen in the backbox.

In 2013, Jersey Jack Pinball released The Wizard of Oz pinball machine, based on the 1939 film. It is the first pinball machine manufactured in the US with a large color display (LCD) in the backbox,^[22] the first widebody pinball machine since 1994^[23] and the first new US pinball machine not made by Stern Pinball since 2001.^[24] This game was followed by The Hobbit^[25] in 2016 (based on The Hobbit film series), Dialed In!^[26] in 2017^[27][28] (an original theme designed by Pat Lawlor which included bluetooth technology that enabled flipper control from a smart phone^[29] and a camera built into the backbox for taking selfies), Pirates of the Caribbean^[30] (based on the Pirates of the Caribbean film series) in 2018, Willy Wonka & The Chocolate Factory^[31] (based on the movie Willy Wonka & the Chocolate Factory from 1971) in 2019, Guns n' Roses in 2020, Toy Story 4 (based on the movie Toy Story 4) in 2022 and The Godfather^[32] (based on The Godfather film series) in 2023.

In 2013, the Chicago Gaming Company announced the creation of a remake of Medieval Madness.^[33][34][35] This was later followed by a 2017 release of a remake of Attack from Mars, a 2018 release of a remake of Monster Bash and a 2021 release of a remake of Cactus Canyon. They would announce their first original title, Pulp Fiction, based on the film Pulp Fiction, in 2023.^[36]

In 2014, the new pinball manufacturer Spooky Pinball released their first game America's Most Haunted.^[37] This was followed by a few more themed, original, and contracted titles.

In 2015, the new British pinball manufacturer Heighway Pinball released the racing themed pinball machine Full Throttle.^[38] The game has an LCD screen for scores, info, and animations located in the playfield surface at player's eye view.^[39] The game was designed with modularity in mind so that the playfield and artwork could be swapped out for future game titles. Heighway Pinball's second title, Alien,^[40] was released in 2017^[41][42] and was based on the Alien and Aliens films. Due to internal company issues,^[43] Heighway Pinball ceased manufacturing operations and closed its doors in April 2018.^[44]

In 2016, Dutch Pinball, based in the Netherlands, released their first game The Big Lebowski, based on the 1998 film, The Big Lebowski.^[45]

In 2017, Multimorphic began shipping its pinball machine platform after several years of development.^[46] It is a modular design where different games can be swapped into the cabinet. It also has a large interactive display as the playfield surface, which differs from all prior pinball machines traditionally made of plywood and embedded with translucent plastic inserts for lighting.

In 2017, American Pinball released its first production game, Houdini (2017), followed by Oktoberfest (2018), Hot Wheels (2020), Legends of Valhalla (2020), and Galactic Tank Force (2023).

In 2022 Flutter released an online pinball game. That same year Google released an Easter Egg pinball game on IOS.^[47]

Relation to gambling

External videos
When Pinball was Illegal, Retro Report Voices, 2:12, Retro Report[48]

Pinball machines, like many other mechanical games, were sometimes used as gambling devices.^[49] Some pinball machines, such as Bally's "bingos", featured a grid on the backglass scoring area with spaces corresponding to targets or holes on the playfield. Free games could be won if the player could get the balls to land in a winning pattern; however, doing this was nearly random, and a common use for such machines was for gambling. Other machines allowed players to win and accumulate large numbers of "free games" which could then be cashed out for money with the location owner. Later, this type of feature was discontinued to legitimize the machines, and to avoid legal problems in areas where awarding free games was considered illegal, some games, called Add-A-Ball, did away with the free game feature, instead giving players extra balls to play (between 5 and 25 in most cases). These extra balls were indicated via lighted graphics in the backglass or by a ball count wheel, but in some areas that was disallowed, and some games were shipped with a sticker to cover the counters.

Pinball was banned beginning in the early 1940s until 1976 in New York City.^[50] New York mayor Fiorello La Guardia was responsible for the ban, believing that it robbed school children of their hard-earned nickels and dimes.^[50][51] La Guardia spearheaded major raids throughout the city, collecting thousands of machines. The mayor participated with police in destroying machines with sledgehammers before dumping the remnants into the city's rivers.^[51]

The ban ended when Roger Sharpe (a star witness for the AMOA – Amusement and Music Operators Association) testified in April 1976 before a committee in a Manhattan courtroom that pinball games had become games of skill and were not games of chance (which are more closely associated with gambling). He began to play one of two games set up in the courtroom, and – in a move he compares to Babe Ruth's home run in the 1932 World Series – called out precisely what he was going to shoot for, and then proceeded to do so. Astonished committee members reportedly voted to remove the ban, which was followed in other cities. (Sharpe reportedly acknowledges, in a self-deprecating manner, his courtroom shot was by sheer luck although there was admittedly skill involved in what he did.)^[52]

Like New York, Los Angeles banned pinball machines in 1939. The ban was overturned by the Supreme Court of California in 1974 because (1) if pinball machines were games of chance, the ordinance was preempted by state law governing games of chance in general, and (2) if they were games of skill, the ordinance was unconstitutional as a denial of the equal protection of the laws.^[53] Although it was rarely enforced, Chicago's ban on pinball lasted three decades and ended in 1976. Philadelphia and Salt Lake City also had similar bans.^[54][55] Regardless of these events, some towns in America still have such bans on their books; the town of Kokomo, Indiana lifted its ordinance banning pinball in December 2016.^[56]

Another close relative of pinball is pachinko, a gambling game played in Japan. Although they share a common ancestry, the games are very different. Pachinko involves shooting many small balls repeatedly into a nearly vertical playfield, while pinball is about manipulating the small number of balls currently in play on a near-horizontal playfield.

Cabinet

The cabinet of a pinball machine is the (traditionally wooden) frame usually shaped like a box, with the playfield laid inside.

Backbox/head

One identifiable attribute of the pinball machine is the cabinet design that contains the mechanical, electrical and electronic parts, assemblies and wires. The modern cabinet consists of two major items. The 'backbox', 'head', or 'lightbox' is the vertical box atop the lower cabinet opposite the player's position. It usually consists of a wooden box with colorful graphics on the side and a large 'backglass' in the front. The backglass usually has very stylized graphics related to or depicting the theme of the game, and also the game's name (and sometimes the manufacture year). The backglass is the game's 'advertisement', intended to catch the eye of passersby and entice gameplay. Many backglasses are beautifully illustrated and approach fine illustration or fine art quality. The silkscreened graphics are partially translucent and have small lights mounted in strategic locations to highlight parts of the artwork and light up scores, the ball currently in play, which player's turn it is (on a multi-player game), and so on. The electromechanical (EM) heads often have 'animation' or moving parts incorporated into the backglass and spring to life if the player achieves the required sequence on the playfield to activate it. Most games have an "insert board" between the backglass and controls that have lights to highlight portions of the backglass artwork or game name or other mechanical devices or displays.

The electromechanical (EM) heads contain the score reels, relays and stepper units that control the scores and other sequencing operations dealing with players, balls, scores, credits and so forth. Most EM backglasses are removed from the rear of the head where a lever will release it so it can be leaned back and carefully sliding it up and out. The newer solid state game heads contain most circuit boards and digital displays that perform the same functions as their EM predecessors, but much faster and with exponentially higher capacity. Newer games may have digital displays (some with alpha-numeric digit displays) or a dot-matrix display (DMD-often used to describe the era of the 90s) and speakers. All games have some sort of cabling connecting the head to the rest of the game. The heads of all games will have 2-4 bolts securing them to the lower cabinet. Newer games have pivot brackets that allow them to be folded down for easier transport. The EMs will have a tin panel in the back of the head with a lock to unlatch for service. Newer games are serviced from the front. Typically they will have a lock on the side of the head, or centered above the backglass to unlatch.

Lower cabinet

The EM lower cabinet contains fuses, relays, stepper units and a score motor, among other things, mounted to a Mechanical Board which is mounted to the cabinet floor. The Mechanical Board is mounted to the cabinet floor with bolts to be removed for service if necessary. Just inside and under the coin door is the cash box.

The modern lower cabinet is mostly empty. Power cord, transformer, tilt mechs, diagnostic switches, speaker(s), wiring harnesses, flipper buttons. Both types of cabinets have four legs at each corner, typically secured with acorn head bolts that mate with a threaded plate attached to the inside corner brace. Older games have wooden legs, while modern games have many finishes on metal legs, with Chrome and black powder coat popular choices. Legs should have adjustable casters at the bottom to adjust the pitch (rear-to-front angle) and level (side-to-side evenness). Some modern games are fitted with a small "bubble level" by the ball plunger.

Playfield

The playfield is a planar surface inclined upward, usually at six and a half degrees,^[57] away from the player, and includes multiple targets and scoring objectives. Some operators intentionally extend threaded levelers on the rear legs and/or shorten or remove the levelers on the front legs to create additional incline in the playfield, making the ball move faster and harder to play.

The ball is put into play by use of the plunger, a spring-loaded rod that strikes the ball as it rests in an entry lane, or as in some newer games, by a button that signals the game logic to fire a solenoid that strikes the ball. With both devices the result is the same: The ball is propelled upwards onto the playfield. Once a ball is in play, it tends to move downward towards the player, although the ball can move in any direction, sometimes unpredictably, due to contact with objects on the playfield or by the player's actions. To return the ball to the upper part of the playfield, the player uses one or more flippers.

Manipulation of the ball may also be accomplished by various tricks, such as "nudging". However, excessive nudging is generally penalized by losing the current player's turn (known as tilting) or ending of the entire game when the nudging is particularly violent (known as slam tilting). This penalty was instituted because nudging the machine too much may damage it or result in unearned play and scoring that wears game parts. Many games also have a slam tilt in the bottom of the lower cabinet to end the game if the cabinet is raised and dropped to the floor in an attempt to trigger the coin counting switch falsely.

Plunger

The plunger is a spring-loaded rod with a small handle, used to propel the ball into the playfield. The player can control the amount of force used for launching by pulling the plunger a certain distance (thus changing the spring compression). This is often used for a "skill shot", in which a player attempts to launch a ball so that it exactly hits a specified target. Once the ball is in motion in the main area of the playfield, the plunger is not used again until another ball must be brought onto the playfield. An electronically controlled launcher is sometimes substituted for the plunger in modern machines. The shape of the ball launch button that replaces the plunger may be modified to fit the aesthetics of a particular game's theme, such as being made to look like the trigger of a gun in a game with a military or action-hero theme.

Flippers

Flippers allow the player to redirect the ball.

The flippers are one or more mechanically or electromechanically (solenoid) controlled levers, roughly 3 to 7 cm (1+1⁄4 to 2+3⁄4 in) in length, used for redirecting the ball up the playfield. They are the main control that the player has over the ball, usually by corresponding pushbuttons on the cabinet's sides. They can primarily be switched fully on, sometimes with two different strengths for thrusting the flipper up and for holding it in position.^[58] Careful timing of this limited positional control allows the player to direct the ball in a range of directions with various levels of velocity and spin. With the flippers, the player attempts to move the ball to hit various types of scoring targets, and to keep the ball from disappearing off the bottom of the playfield.

The very first pinball games appeared in the early 1930s and did not have flippers; after launching the ball simply proceeded down the playfield, directed by static nails (or "pins") to one of several scoring areas. (These pins gave the game its name.) In 1947, the first mechanical flippers appeared on Gottlieb's Humpty Dumpty^[59] and by the early 1950s, the two-flipper configuration at the bottom above the center drain had become standard. Some pinball models also have a third or fourth flipper. A few later machines even have flippers that the machine's software could operate independently of the flipper button. During "Thing Flips" on The Addams Family pinball machine, the upper-left flipper automatically triggers a brief moment after the ball passes an optical sensor just above the flipper. Very few machines came with curve shaped banana flippers.

The introduction of flippers ushered in the "golden age" of pinball, where the fierce competition between the various pinball manufacturers led to constant innovation in the field. Various types of stationary and moving targets were added, spinning scoring reels replaced games featuring static scores lit from behind. Multiplayer scores were added soon after, and then bells and other noise-makers, all of which began to make pinball less a game and more of an experience. The flippers have loaned pinball its common name in many languages, where the game is known mainly as "flipper".

Bumpers

Bumpers are round knobs that, when hit, will actively push the ball away. There is also an earlier variety of bumper (known as a dead bumper or passive bumper) that does not propel the ball away; most bumpers on machines built since the 1960s are active bumpers, variously called "pop bumpers", "thumper bumpers", "jet bumpers", or "turbo bumpers". Most recent games include a set of pop bumpers, usually three, sometimes more or fewer depending on the designer's goals. Bumpers predate flippers, and active bumpers served to add interest and complexity to older games.

Pop bumpers are operated by a switch connected to a ring surrounding the bottom circumference of the bumper that is suspended several millimeters above the playfield surface. When the ball rolls over this ring and forces one side of it down, a switch is closed that activates the bumper's solenoid. This pulls down a tapered ring surrounding the central post of the bumper that pushes downward and outward on the ball, propelling it away.

Kickers and slingshots

Slingshots have rubber bands around them. Switches behind the rubber detect the ball's impact and a solenoid-driven lever kicks it away.

Kickers and slingshots are rubber pads that propel the ball away upon impact, like bumpers, but are usually a horizontal side of a wall. Every recent pinball machine includes slingshots to the upper left and upper right of the lowest set of flippers; older games used more experimental arrangements. They operate similarly to pop bumpers, with a switch on each side of a solenoid-operated lever arm in a typical arrangement. The switches are closed by ball contact with the rubber on the kicker's face, which activates the solenoid.

Early pinball machines typically had full solenoid current passing through trigger switches for all types of solenoids, from kickers to pop bumpers to the flippers themselves. This caused arcing across switch contacts and rapid contact fouling and failure. As electronics were gradually implemented in pinball design, solenoids began to be switched by power transistors under software control to lower switch voltage and current, vastly extend switch service lifetime, and add flexibility to game design.

The smaller, lower-powered solenoids were first to be transistorized, followed later by the higher-current solenoids as the price, performance, and reliability of power transistors improved over the years.

Targets

Stationary targets detect the ball's impact and typically increment the player's score.

• Stationary Targets: These are static targets that simply record when a ball strikes them. These are generally the simplest playfield elements. They are also known as spot targets or standup targets.
• Bullseye Targets: These are static targets that have two concentric elements, similar to a stationary target. Hitting the outer ring usually scores lower than hitting the center bull's eye. They are found chiefly in older electro-mechanical games.
• Drop targets: These are targets that drop below the playfield when hit. Eliminating an entire row in this manner may lead to any of various features. Once an entire bank of drop targets is hit, the bank may reset or pop back up. Alternatively, the drop targets can be placed in front of other targets, requiring the drop target to be knocked down before the targets behind can be hit, or the drop target may only pop up at specific times to deny the player the ability to shoot the ball into whatever is behind it. If used in the latter way, the target is usually blocking a lane or ramp.
• Kicking Target: Used rarely, these targets look like stationary targets, but when hit, they kick the ball away in the opposite direction, much like a slingshot or bumper.
• Vari-Target: These targets award different points depending on how hard the target was hit. It is a metal arm that pivots under the playfield. When a ball hits it, it ratchets back sometimes, resetting immediately or resetting only after it is hit all the way back. A large sum of points is usually awarded when the target is hit back all the way with one strike of the ball.

Holes and saucers

• Holes: The player directs the ball into a hole. In modern games, there are both vertical and horizontal holes (also called scoops), and the game may include mechanisms to move the ball between them. A "gobble hole" is sometimes included in some older games, which does not return the ball, but gives a large bonus or a game feature, which may be the ball itself.
• Saucers: A shallow hole with a kicker inside. The ball remains visible on the playfield and is kicked out straight up (usually into a duct or rail chute) or sideways back onto the playfield.

Initially, holes and saucers worked by using tubes behind the playing field, with a pin at the top to hold the ball for later drops. Another version of the tube uses two spinning wheels to transfer the ball from hole to hole. Newer versions use an electronic track with a carriage or an electromagnet to pull the ball between holes.

Spinners and rollovers

Rollovers detect when the ball passes over them.

• Spinners: A ball can push through a flat surface hinged in the middle, causing it to spin; each rotation adds points.
• Rollovers: These are targets activated when a ball rolls over them. Often a series of rollover targets are placed side-by-side and with dividers between them forming "lanes"; the player must guide the ball to particular lanes (or to all lanes) to complete an objective. Such lanes are frequently placed at the bottom sides of the playfield: "inlanes" feed the ball back to the flippers, "outlanes" cause the ball to drain immediately. On many machines, outlanes can have extra balls or "specials" lit to play the same role as the older gobble holes.
• Whirlwind Spinner(s): Used in some games, a whirlwind spinner is a rapidly rotating (often rubberized) disk on the playfield that momentarily "grabs" the ball and throws it in a random direction. Some games couple a whirlwind spinner with a magnet placed in the center, although Data East seems to be the only manufacturer to do so. Bally's "Fireball" and Chicago Coin's "Casino" were popular games with a whirlwind spinner.

Switches, gates, and stoppers

• Switch: A switch is an area that is blocked off after the ball passes through it once. An example of this is the initial firing lane: as a ball passes through the firing lane, it hits a switch and cannot reenter that chute.
• Gate: This block will allow balls to come through one way but will block the ball if it is going the other way.
• Stopper: Also called a magic post, this is a small pole most often found centered between and just below the lowest set of flippers and also rarely next to the outlanes. When activated (typically by hitting a specific target or targets), the pole ascends from inside the machine, blocking the area between the flippers for a limited time, making it more difficult to drain and lose the ball. After time expires, it returns to its resting place just below the playfield.

Ramps

A wire ramp along which the ball can travel

Ramps are inclined planes with a gentle enough slope that the ball may travel along it. The player attempts to direct the ball with enough force to make it to the top of the ramp and down the other side. If the player succeeds, a "ramp shot" has been made. Ramps frequently end so that the ball goes to a flipper so one can make several ramp shots in a row. The number of ramp shots scored in a game is often tallied, and reaching certain numbers may lead to various game features. At other times, the ramps will go to smaller "mini-playfields" (small playfields, usually raised above the main game surface, with special goals or scoring).

Toys, magnets and captive balls

• Toys: Toys are various items on, above, or beneath the playfield (items beneath the playfield visible through windows) or attached to the cabinet (usually to the backbox). Usually, each toy is unique to the machine it was made for, and reflects the game's theme. They may be visual only, and have no effect on gameplay; they may be alternate ways of performing common game functions (for example, instead of using a drop hole to hold the ball, a hand or claw might reach out, grab the ball, and capture it that way); or they may be an integral part of the game rules and play (for instance, having a smaller playfield over the main playfield that can be tilted right and left by the player, using the flipper buttons).
• Electromagnets: Some machines feature electrically operated magnets below the playfield to affect the ball's speed and trajectory according to the current state of gameplay. This may be done to make the ball's movement unpredictable, temporarily halt the ball (as a ball saver, for example), or otherwise control the ball by non-mechanical means. Electromagnets may also be used in above-playfield elements (often as part of the playfield toys) to grab the ball and move it elsewhere (onto a mini-playfield, for example). The Williams machine The Twilight Zone featured a mini-playfield that used electromagnets controlled by the flipper buttons, allowing the player to flip the ball on the mini-playfield, essentially working as invisible flippers. Contrary to a popular myth, there are no professionally produced pinball machines that contain magnets under the playfield intended to clandestinely make gameplay harder or increase ball losses.^[60]
• Captive balls: Sometimes a ball can move around only within a confined area. A typical application of this has a short lane on the playfield with a narrow opening, inside which a captive ball is held. The player can strike this captive ball with the ball in play, pushing it along the lane to activate a rollover switch or target. In games such as Theatre of Magic, captive balls sometimes have what is called a "Newton Ball", which is a stationary ball adjacent to a free ball in a small lane. The ball being played strikes the Newton ball which, in turn, transfers its momentum to the adjacent ball, which causes it to move.

Backglass

The backglass is a vertical graphic panel mounted on the front of the backbox, which is the upright box at the top back of the machine. The backglass contains the name of the machine and eye-catching graphics. The score displays (lights, mechanical wheels, an LED display, or a dot-matrix display depending on the era) would be on the backglass, and sometimes also a mechanical device tied to gameplay, for example, elevator doors that opened on an image or a woman swatting a cat with a broom such as on Williams' 1989 Bad Cats. For older games, the backglass image is screen printed in layers on the reverse side of a piece of glass; in more recent games, the image is imprinted into a translucent piece of plastic-like material called a translite which is mounted behind a piece of glass and which is easily removable. The earliest games did not have backglasses or backboxes and were little more than playfields in boxes. Games are generally built around a particular theme, such as a sport or character and the backglass art reflects this theme to attract the attention of players. Recent machines are typically tied into other enterprises such as a popular film series, toy, or brand name. The entire machine is designed to be as eye-catching as possible to attract players and their money; every possible space is filled with colorful graphics, blinking lights, and themed objects. The backglass is usually the first artwork the players see from a distance. Since the artistic value of the backglass may be quite impressive, it is not uncommon for enthusiasts to use a deep frame around a backglass (lighted from behind) and hang it as art after the remainder of the game is discarded.

Special scores

• High score lists: If a player attains one of the highest scores ever (or the highest score on a given day), they are invited to add their initials to a displayed list of high-scorers on that particular machine. "Bragging rights" associated with being on the high-score list are a powerful incentive for experienced players to master a new machine.

Pinball designers also entice players with the chance to win a free game or credit. Ways to get a free game might include the following:

• Replay: A free game is awarded if the player exceeds a specified score. Some machines allow the operator to set this score to increase with each consecutive game in which the replay score is achieved, in order to prevent a skilled player from gaining virtually unlimited play on one credit by simply achieving the same replay score in every game.
• Special: A mechanism to get a free game during play is usually called a "special". Typically, some hard-to-reach feature of the game will light the outlanes (the areas to the extreme left and right of the flippers) for special. Since the outlanes always lose the ball, having "special" there makes it worth shooting for them (and is usually the only time, if this is the case).
• Match: At the end of the game, if a set digit of the player's score matches a random digit, a free game is awarded.^[72] In earlier machines, the set digit was usually the ones place; after a phenomenon often referred to as score inflation had happened (causing almost all scores to end in 0), the set digit was usually the tens place. The chances of a match appear to be 1 in 10, but the operator can alter this probability – the default is usually 7% in all modern Williams and Bally games for example. Other non-numeric methods are sometimes used to award a match.
• High Score: Bally/Midway, Williams and Stern Pinball machines award 1–3 free games if a player gets on the high score list. Typically, one or two credits are awarded for a 1st–4th place listing, and three for the Grand Champion.

When a free game is won, Williams and Bally/Midway machines typically makes a single loud bang, most often with a solenoid that strikes a piece of metal, or the side of the cabinet, with a rod, known as a knocker, or less commonly with loudspeakers. "Knocking" is the act of winning a free game when the knocker makes the loud and distinctive noise.

Nudging

Players can influence the movement of the ball by moving or bumping the pinball machine, a technique known as "nudging" or "shaking". After some experience in playing a certain machine, a skillful player is able to nudge the machine to make the ball bounce harder from a bumper or go in a certain direction. A very skillful player can shake the machine and cause the ball to bounce back and forth and prevent it from "draining".

There are tilt mechanisms which guard against excessive manipulation of this sort. The mechanisms generally include:

• a grounded plumb bob centered in an electrified metal ring – when the machine is jostled or shaken too far or too hard, the bob contacts the ring, completing a circuit. The bob is usually cone-shaped allowing the operator to slide it vertically, controlling the sensitivity.
• an electrified ball on a slight ramp with a grounded post at the top of the ramp – when the front of the machine is lifted (literally, tilted) too high, the ball rolls to the top of the ramp and completes the circuit.
• an impact sensor – usually located on the coin door, the playfield and/or the cabinet itself.

When any of these sensors is activated, the game registers a "tilt" and the lights go out, solenoids for the flippers no longer work, and other playfield systems become inoperative so that the ball can do nothing other than roll down the playfield directly to the drain. A tilt will usually result in loss of bonus points earned by the player during that ball; the game is automatically over if it is the last ball and the player has no extra ball. Older games would immediately end the ball in play on a tilt. Modern games give tilt warnings before sacrificing the ball in play. The number of tilt warnings can be adjusted by the operator of the machine. Until recently most games also had a "slam tilt" switch which guarded against kicking or slamming the coin mechanism, or for overly aggressive behavior with the machine, which could give a false indication that a coin had been inserted, thereby giving a free game or credit. This feature was recently taken out by default in new Stern S.A.M System games, but can be added as an option. A slam tilt will typically end the current game for all players.

Trapping

Skilled players can also hold a ball in place with the flipper, giving them more control over where they want to place the ball when they shoot it forward. This is known as trapping. This technique involves catching the ball in the corner between the base of the flipper and the wall to its side, just as the ball falls towards the flipper; the flipper is then released, which allows the ball to roll slowly downward against the flipper. The player then chooses the moment to hit the flipper again, timing the shot as the ball slides slowly against the flipper. Multi-ball games, in particular, reward trapping techniques. Usually this is done by trapping one or more balls out of play with one flipper, then using the other flipper to score points with the remaining ball or balls.

Once a player has successfully trapped a ball, they may then attempt to "juggle" the ball to the other flipper. This is done by tapping the flipper button quickly enough so that the trapped ball is knocked back at an angle of less than 90 degrees into the bottom of the nearest slingshot. The ball will then often bounce across the playfield to the other flipper, where the ball may then be hit (or trapped) by the opposite flipper.

Occasionally a pinball machine will have a pin or post placed directly between the two bottom flippers. When this feature is present, the advanced player may then attempt to perform a "chill maneuver" when the ball is heading directly toward the pin by opting not to hit a flipper. If successful, this will cause the ball to bounce up and back into play. A related move, the "dead flipper pass", is performed by not flipping when a ball is heading toward a flipper. If done properly, the ball will bounce off the "dead" flipper, across to the other flipper, where it may be trapped and controlled.

Solenoids

• Solenoids or coils: These are found in every modern pinball machine since the flipper age. They are usually hidden under the playfield, or covered by playfield components. By applying power to the coil, the magnetic field created by electromagnetism causes a metal object (usually called a plunger) to move. The plunger is then connected mechanically to a feature or accessory on the playfield.

Flipper solenoids contain two coil windings in one package; a short, heavy gage 'power' winding to give the flipper its initial thrust up, and a long, light gage 'hold' winding that uses lower power (and creates far less heat) and essentially just holds the flipper up allowing the player to capture the ball in the inlane for more precise aiming. As the flipper nears the end of its upward travel, a switch under the flipper disconnects the power-winding and leaves only the second sustain winding to hold the flipper up in place. If this switch fails 'open' the flipper will be too weak to be usable, since only the weak winding is available. If it fails 'closed' the coil will overheat and destroy itself, since both windings will hold the flipper at the top of its stroke.

Solenoids also control pop-bumpers, kickbacks, drop target resets, and many other features on the machine. These solenoid coils contain a single coil winding. The plunger size and wire gage & length are matched to the strength required for each coil to do its work, so some types are repeated throughout the game, some are not.

All solenoids and coils used on microprocessor games include a special reverse-biased diode to eliminate a high-voltage pulse of reverse EMF (electromotive force). Without this diode, when the solenoid is de-energized, the magnetic field that was built up in the coil collapses and generates a brief, high-voltage pulse backward into the wiring, capable of destroying the solid-state components used to control the solenoid. Proper wiring polarity must be retained during coil replacement or this diode will act as a dead short, immediately destroying electronic switches. Older electromechanical AC game solenoids do not require this diode, since they were controlled with mechanical switches. However, electromechanical games running on DC do require diodes to protect the rectifier.^[73]

All but very old games use low DC voltages to power the solenoids and electronics (or relays). Some microprocessor games use high voltages (potentially hazardous) for the score displays. Very early games used low-voltage AC power for solenoids, requiring fewer components, but AC is less efficient for powering solenoids, causing heavier wiring and slower performance. For locations that suffer from low AC wall outlet voltage, additional taps may be provided on the AC transformer in electromechanical games to permit raising the game's DC voltage levels, thus strengthening the solenoids. Microprocessor games have electronic power supplies that automatically compensate for inaccurate AC supply voltages.

Historically, pinball machines have employed a central fixed I/O board connected to the primary CPU controlled by a custom microcontroller platform running an in-house operating system. For a variety of reasons that include thermal flow, reliability, vibration reduction and serviceability, I/O electronics have been located in the upper backbox of the game, requiring significant custom wiring harnesses to connect the central I/O board to the playfield devices.

A typical pinball machine I/O mix includes 16 to 24 outputs for driving solenoids, motors, electromagnets and other mechanical devices in the game. These devices can draw up to 500 W momentarily and operate at voltages up to 50 Vdc. There is also individually controlled lighting that consists of 64 to 96 individually addressable lights. Recently developed games have switched from incandescent bulbs to LEDs. And there is general illumination lighting that comprises two or more higher-power light strings connected and controlled in parallel for providing broad illumination to the playfield and backbox artwork. Additionally, 12 to 24 high-impulse lighting outputs, traditionally incandescent but now LED, provide flash effects within the game. Traditionally, these were often controlled by solenoid-level drivers.

A game typically includes 64 to 96 TTL-level inputs from a variety of sensors such as mechanical leaf switches, optical sensors and electromagnetic sensors. Occasionally extra signal conditioning is necessary to adapt custom sensors, such as eddy sensors, to the system TTL inputs.

Recently, some pinball manufacturers have replaced some of the discrete control wiring with standard communication buses. In one case, the pinball control system might include a custom embedded network node bus, a custom embedded Linux-based software stack, and a 48-V embedded power distribution system.^[74]

Custom machines

A restored Terminator 2 pinball machine with all metal parts plated with chrome

Some hobbyists and small companies modify existing pinball machines or create their own custom pinball machines. Some want, for example, a game with a specific subject or theme that cannot be bought in this form or was never built at all.^[75] Some custom games are built by using the programmable P-ROC controller board.^[76] Modifications include the use of ColorDMD that is used to replace the standard mono color dot-matrix displays^[77] or the addition of features, e.g. figures or other toys.^[78]

A few notable examples of custom pinball machines include a Ghostbusters theme machine,^[79] a Matrix style game,^[80] Bill Paxton Pinball,^[81] Sonic, Star Fox, Predator, and Iron man^[82] machines.^[76]

Data East was one of the few regular pinball companies that manufactured custom pinball games (e.g. for Aaron Spelling, Michael Jordan and the movie Richie Rich), though these were basically mods of existing or soon to be released pinball machines (e.g. Lethal Weapon 3 or The Who's Tommy Pinball Wizard).