Call of Duty in the context of "Call of Duty 3"

A multiplayer video game is a video game in which more than one person can play in the same game environment at the same time, either locally on the same computing system (couch co-op), on different computing systems via a local area network, or via a wide area network, most commonly the Internet (e.g. World of Warcraft, Call of Duty, DayZ). Multiplayer games usually require players to share a single game system or use networking technology to play together over a greater distance; players may compete against one or more human contestants, work cooperatively with a human partner to achieve a common goal, or supervise other players' activity. Due to multiplayer games allowing players to interact with other individuals, they provide an element of social communication absent from single-player games.

The history of multiplayer video games extends over several decades, tracing back to the emergence of electronic gaming in the mid-20th century. One of the earliest instances of multiplayer interaction was witnessed with the development of Spacewar! in 1962 for the DEC PDP-1 computer by Steve Russell and colleagues at the MIT. During the late 1970s and early 1980s, multiplayer gaming gained momentum within the arcade scene with classics like Pong and Tank. The transition to home gaming consoles in the 1980s further popularized multiplayer gaming. Titles like Super Mario Bros. for the NES and Golden Axe for the Sega Genesis introduced cooperative and competitive gameplay. Additionally, LAN gaming emerged in the late 1980s, enabling players to connect multiple computers for multiplayer gameplay, popularized by titles like Doom and Warcraft: Orcs & Humans. Players can also play together in the same room using splitscreen.

Activision Blizzard, Inc. is an American video game holding company based in Santa Monica, California. Activision Blizzard currently includes three operating units: Activision, Blizzard Entertainment and King.

Founded in July 2008 through the merger of Activision, Inc. and Vivendi Games, the company owns and operates additional subsidiary studios, as part of Activision, including Infinity Ward, Treyarch, and Sledgehammer Games. Among major intellectual properties produced by Activision Blizzard are Call of Duty, Crash Bandicoot, Guitar Hero, Skylanders, Spyro, Tony Hawk's, Diablo, Hearthstone, Heroes of the Storm, Overwatch, StarCraft, World of Warcraft, and Candy Crush Saga. Under Blizzard Entertainment, it invested in esports initiatives around several of its games, most notably Overwatch and Call of Duty. Activision Blizzard's titles have broken a number of release records. As of March 2018, it was the largest game company in the Americas and Europe in terms of revenue and market capitalization.

On January 18, 2022, Microsoft announced its intent to acquire Activision Blizzard for $68.7 billion. The acquisition was completed on October 13, 2023, with its total cost amounting to $75.4 billion. Under the terms of the agreement, Microsoft brought Activision Blizzard under its Microsoft Gaming business unit as a sibling division to Xbox Game Studios and ZeniMax Media. With it, Microsoft gained ownership of several franchises under Activision, Blizzard Entertainment, and King, including Call of Duty, Crash Bandicoot, Spyro, Warcraft, StarCraft, Diablo, Overwatch, and Candy Crush. As of 2023, the acquisition is the largest video game acquisition by transaction value in history.

Following shareholder approval of the acquisition, the merger was reviewed by several national anti-trust bodies, with early approvals granted by the European Commission and China's State Administration for Market Regulation (SAMR), among others. The United States' Federal Trade Commission (FTC) and the United Kingdom's Competition and Markets Authority (CMA) issued formal challenges to the acquisition. Sony also criticized the merger, concerned that Microsoft would make the lucrative Call of Duty franchise exclusive to the Xbox platform, though Microsoft committed to non-exclusivity through 2033. The FTC withdrew its request after courts did not find their anti-trust compelling to block the merger, while Microsoft offered to offload its cloud gaming support for Activision Blizzard's games for ten years to Ubisoft to appease the CMA.

Infinity Ward, Inc. is an American video game developer. They developed the video game Call of Duty, along with seven other installments in the Call of Duty series. Vince Zampella, Grant Collier, and Jason West established Infinity Ward in 2002 after working at 2015, Inc. previously. All of the 22 original team members of Infinity Ward came from the team that had worked on Medal of Honor: Allied Assault while at 2015, Inc. Activision helped fund Infinity Ward in its early days, buying up 30 percent of the company, before eventually fully acquiring them. The studio's first game, World War II shooter Call of Duty, was released on the PC in 2003. The day after the game was released, Activision bought the rest of Infinity Ward, signing employees to long-term contracts. Infinity Ward went on to make Call of Duty 2, Call of Duty 4: Modern Warfare, Call of Duty: Modern Warfare 2, Call of Duty: Modern Warfare 3, Call of Duty: Ghosts, Call of Duty: Infinite Warfare, the Modern Warfare reboot, and its sequel.

Co-founder Collier left the company in early 2009 to join parent company Activision. In 2010, West and Zampella were fired by Activision for "breaches of contract and insubordination", they soon founded a game studio called Respawn Entertainment. On May 3, 2014, Neversoft was merged into Infinity Ward.

Treyarch Corporation (/ˈtreɪɑːrk/ TRAY-ark; formerly Treyarch Invention LLC) is an American video game developer based in Los Angeles with additional studio locations in Vancouver, Canada; and Austin, Texas. Founded in 1996 by Peter Akemann and Doğan Köslü, it was acquired by Activision in 2001. The studio is known for its work for the Call of Duty series, which it develops alongside Infinity Ward, Sledgehammer Games, and Raven Software.

Sledgehammer Games, Inc. is an American video game developer company formed in 2009 by Glen Schofield and Michael Condrey. The pair formerly worked at EA Redwood Shores and are responsible for the creation of Dead Space. The company is based in Foster City, California. The studio has developed and co-developed various video games in the Call of Duty series. The company is owned by Activision.

In 2024, Sledgehammer Games closed its office in California, and employees were to be working from home until the end of that year. In that year, thirty percent of employees were also laid off as part of a restructuring within Microsoft Gaming.

Call of Duty is a 2003 first-person shooter game developed by Infinity Ward and published by Activision. It is the first installment in the Call of Duty franchise, released on October 29, 2003, for Microsoft Windows. The game simulates infantry and combined arms warfare of World War II using a modified version of the id Tech 3 engine. Much of its theme and gameplay is similar to the Medal of Honor series; however, Call of Duty showcases multiple viewpoints staged in the American, British, and Soviet campaigns of World War II in Europe.

The game introduced a new take on AI-controlled allies who support the player during missions and react to situational changes during gameplay. This led to a greater emphasis on squad-based play as opposed to the "lone wolf" approach often portrayed in earlier first-person shooter games. Much of Infinity Ward's development team consisted of members who helped develop Medal of Honor: Allied Assault. On release, the game received universal acclaim and won several Game of the Year awards. Retrospective assessments have been more negative, with many critics saying the game aged poorly; it has placed low in lists ranking the series' games.

Call of Duty 2 is a 2005 first-person shooter game developed by Infinity Ward and published by Activision in most regions of the world. It is the second installment of the Call of Duty series. Announced by Activision on April 7, 2005, the game was released for Microsoft Windows on October 25, 2005, and as a launch title for the Xbox 360 on November 22, 2005. Other versions were eventually released for OS X, mobile phones, and Pocket PCs.

The game is set during World War II and the campaign mode is experienced through the perspectives of four soldiers: one in the Red Army, one in the United States Army, and two in the British Army. It contains four individual campaigns, split into three stories, with a total of 27 missions. Many features were added and changed from the original Call of Duty, notably regenerating health and an icon that indicates a nearby grenade about to explode.