Infinity Ward. (2007). Call of Duty 4: Modern Warfare [Video game]. Activision.

Call of Duty 4: Modern Warfare is a first-person shooter developed by Infinity Ward and published by Activision in 2007. Departing from the series' World War II roots, the game is set in a contemporary setting, focusing on a fictional conflict involving a radical Middle Eastern leader and a Russian ultranationalist. The single-player campaign is experienced through the perspectives of multiple characters, including Sergeant John "Soap" MacTavish of the British SAS and Sergeant Paul Jackson of the U.S. Marine Corps, with missions spanning various global locations.

The gameplay emphasizes modern infantry and combined arms warfare. Players utilize a variety of authentic modern firearms and equipment, each with realistic aiming and recoil mechanics. The campaign features diverse mission types, from all-out assaults to stealth infiltrations, including the notable "All Ghillied Up" mission, where players don a ghillie suit for a covert sniper assignment. The game also introduces a regenerating health system, replacing traditional health packs, encouraging players to seek cover to recover from damage.

The multiplayer component is robust, offering various game modes such as Team Deathmatch and Domination. It introduces a leveling system that allows players to unlock new weapons, attachments, and perks—special abilities that modify gameplay, such as increased bullet damage or the ability to drop a live grenade upon death. The "Create-a-Class" feature enables players to customize loadouts to suit their playstyle. Killstreak rewards, granted for consecutive enemy kills without dying, provide tactical advantages like UAV reconnaissance or airstrikes.

Upon release, Modern Warfare received critical acclaim for its engaging narrative, compelling gameplay, and polished multiplayer experience. It earned numerous Game of the Year awards and significantly influenced the first-person shooter genre, setting new standards for storytelling and online multiplayer modes. The game's success led to two direct sequels, Modern Warfare 2 and Modern Warfare 3, and a remastered version released in 2016. Its impact on gaming culture is profound, with many considering it one of the greatest video games ever made.