Tennis for Two, also known as Computer Tennis, is a video game that copies a tennis match. It was one of the first games ever made during the early history of video games. American physicist William Higinbotham created the game in 1958 for a public exhibition at Brookhaven National Laboratory. He learned that the laboratory’s Donner Model 30 analog computer could copy how objects move through the air with wind. He designed the game in just a few hours, and then he and technician Robert V. Dvorak built it over three weeks. The game was shown on an oscilloscope and played with two special aluminum controllers. Its images showed a side view of a tennis court, and players used a knob on their controller to change the angle of their shots and pressed a button to hit the ball over the net.
The game was very popular during the three-day exhibition, with many people, especially high school students, waiting to play. It was shown again the next year with a bigger oscilloscope screen and a more complex design that could copy different gravity levels. After that, the game was taken apart and mostly forgotten until the late 1970s, when Higinbotham talked about it in court during a legal case between Magnavox and Ralph H. Baer about video game patents. Since then, the game has been recognized as one of the earliest video games. Brookhaven National Laboratory has recreated the original device. Under some definitions, Tennis for Two is considered the first video game because, although it did not use any new technology from earlier games, it was the first computer game made purely for fun rather than for research or to promote technology.
Development
In 1958, American physicist William Higinbotham worked at Brookhaven National Laboratory in Upton, New York, as the head of the instrumentation division. Higinbotham earned a bachelor's degree in physics from Williams College and had previously worked as a technician in the physics department at Cornell University while trying to earn a Ph.D. in physics, but did not complete it. He was the leader of the electronics division in the Manhattan Project from 1943 to 1945 and began working at Brookhaven in 1947, where the lab focused on researching peaceful uses of atomic power. Each year, the lab held a public exhibition with separate days for high school students, college students, and the general public. The exhibition included tours and static displays, but Higinbotham wanted to add an interactive game to make the event more engaging. While reading the manual for a Donner Model 30 analog computer, he discovered it could calculate paths of ballistic missiles or a bouncing ball with wind resistance. He decided to use this ability to create a game. He later said he wanted the game to make the event more fun and show how science helps society.
Higinbotham designed a game using an oscilloscope to display the path of a simulated tennis ball from the side. The computer calculated the ball's path and reversed it when it hit the ground. The game also showed the ball hitting the net if it did not go high enough and changed speed due to air resistance. Two aluminum controllers were attached to the computer, each with a button and a knob. Pressing the button hit the ball, and turning the knob controlled the angle of the shot. He first thought about adding a second knob to control speed, but decided it would be too complex. The device was designed in a few hours and built over three weeks with the help of technician Robert V. Dvorak. Most parts used vacuum tubes and relays, but the circuits for the oscilloscope used transistors, which were starting to replace vacuum tubes in electronics. Excluding the oscilloscope and controller, the game's circuitry took up about the space of a microwave oven.
Presentation
Tennis for Two was first displayed on October 18, 1958. The game’s environment was drawn as a horizontal line to show the tennis court and a short vertical line in the middle to represent the tennis net, viewed from the side. The first player pressed a button on their controller to send a glowing dot, representing the ball, over the net. The ball could hit the net, land on the other side of the court, or go out of bounds. The second player could then hit the ball back using their controller while it was on their side, either before or after it touched the ground. Many visitors waited in line to try the new game during its first showing. Higinbotham later said that "the high schoolers liked it best, you couldn't pull them away from it." Because of the game’s popularity, an improved version was shown the next year. This version included a larger screen (10–17 inches) and different settings for pretend gravity. Players could choose to simulate the gravity of the Moon or Jupiter. Higinbotham called the game "Tennis for Two," but a sign on the 1959 version labeled it "Computer Tennis." After the 1959 display, the game was taken apart so its parts could be used for other purposes.
Legacy
After being taken apart, Tennis for Two was mostly forgotten. It was almost unknown until the late 1970s and early 1980s when Higinbotham was asked to speak in court cases involving Magnavox and Ralph H. Baer’s video game patents. Defense lawyers found the game and tried to prove it was an earlier example of similar technology, which could have canceled Baer’s patents. This effort brought attention to the nearly 20-year-old game, which some believed might be the first video game. In 1982 and 1983, articles in Creative Computing and Video Replay discussed its possible status as the first video game. David H. Ahl, the editor of Creative Computing, had played Tennis for Two at Brookhaven in 1958 and called Higinbotham the "Grandfather of Video Games." Higinbotham himself believed the game was a simple improvement on an earlier program and did not think it deserved special recognition. He preferred to be remembered for his work on nuclear non-proliferation after World War II.
In 1997, a team at Brookhaven recreated the game for its 50th anniversary. The recreation took about three months because some parts were hard to find. This version was later shown at the 2008 celebration of the game’s 50th anniversary. The replica used an analog computer with solid-state devices instead of vacuum tubes, as the original Donner Model 30 had. In 2010, it was replaced with a restored Donner Model 3400 analog computer. In 2011, Stony Brook University created the William A. Higinbotham Game Studies Collection to preserve materials related to Higinbotham’s work and the history of early games. The collection focuses on documenting the development of screen-based games and the contributions of Higinbotham, who invented Tennis for Two in 1958.
Some definitions consider Tennis for Two the first video game. Other early examples include the 1947 cathode-ray tube amusement device, the earliest known interactive electronic game, though it did not use a computer; the 1950 Bertie the Brain, the first game to run on a computer but using light bulbs for a display; and OXO and a draughts game by Christopher Strachey in 1952, the first digital games to show visuals on a screen. Tennis for Two, while not introducing new technology, is unique as the earliest known computer game created purely for entertainment. Earlier games were mainly for research or to show a computer’s power, except for the cathode-ray tube device. This makes Tennis for Two the first video game under some definitions, based on its purpose rather than its technology, and a key moment in video game history.