Gryzor

Contra employs a variety of playing perspectives, which include a standard side view, a pseudo-3D view (in which the player proceeds by shooting and moving towards the background, in addition to left or right) and a fixed screen format (in which the player has their gun aimed upwards by default). Up to two people can play simultaneously, with one player as Bill (the blond-haired commando wearing a white tank top and blue bandana), and the other player as Lance (the shirtless dark-haired commando with a red bandana).

The controls consist of an eight-way joystick and two action buttons for shooting (left) and jumping (right). When one of the protagonists jumps, he curls into a somersault instead of doing a conventional jump like in other games. The joystick controls not only the player's movement while running and jumping, but also his aiming. During side view stages, the player can shoot leftward, rightward or upward while standing, as well as horizontally and diagonally while running.

Contra is set in the distant future of the year 2633 A.D., when the evil Red Falcon Organization have set a base on the fictional Galuga archipelago near New Zealand in a plot to wipe out humanity. Two commandos, Bill Rizer and Lance Bean of the Earth Marine Corp's Contra unit (an elite group of soldiers specializing in guerrilla warfare), are sent to the island to destroy the enemy forces and uncover the true nature of the alien entity controlling them.

The promotional materials for the US arcade version downplays the futuristic setting of the game, with the manual for the later NES and home computer versions changing the game's setting from the future to the present day and the location from Galuga to the Amazon Jungle.

In Japan, the arcade game topped the Game Machine chart for table arcade cabinets in April 1987. In the United Kingdom, Gryzor was a blockbuster hit in the arcades and the home computer versions topped the Gallup charts. In the United States, Contra became one of the top four highest-grossing dedicated arcade games of 1987. The 1988 Nintendo Entertainment System port became and remained widely popular and remembered.

The game sold 2 million units. Much of the game's popularity came from its two-player simultaneous co-op gameplay.

Contra was followed by Super Contra later the same year. It is the only Contra sequel for the arcades developed in-house by Konami. Following the success of the NES adaptations of both the original and its sequel (which was retitled Super C in its American release), subsequent sequels were produced specifically for the home console market such as Contra III: The Alien Wars for the Super NES and Contra: Hard Corps for the Genesis, becoming one of Konami's flagship series. As of 2024, the series has 13 installments.

The music from the arcade version of Contra is one of the soundtracks included in the video game album Konami Game Music Vol.4: A Jax, which was released by Alfa Records on May 10, 1988, in CD (catalog no. 28XA-201), cassette (ALC-22922), and vinyl (ALR-22922).